High integrity die cast parts, custom manufactured, are now available from Five Star Die Casting.
Fivestar Die Casting now offers manufacturers high integrity parts with just-in-time (JIT) domestic sourcing. These high integrity casting processes provide parts with high strength, superior fatigue life and pressure tightness. Five Star's new, fully automated die casting cell enables (1) conventional High Pressure Die Casting (HPDC), (2) Squeeze Casting (SQZ), and (3) Semi-Liquid Process Casting. All casting cells at Fivestar offer vacuum casting capabilities.
At the heart of Five Star's new automated die casting cell is a Buhler 630 SC High Pressure Die Casting machine. This cell is fully automated with a Thermtronix melting/holding furnace, Rimrock autoladle and die spray units, a Sterlco die thermal control unit, and an ABB five axis robot for part extraction/trim press loading.
"Five Star Die Casting gives OEM manufacturers a better, higher quality sourcing option to fulfill their high integrity die cast part needs," reports Alan Koch, general manager. "Our state of the art die casting technology and processes assures OEM's of components that meet high strength and demanding performance requirements."
Five Star Die Casting also offers complete value added services through its affiliated company, Marshall Manufacturing. These services include CNC Swiss machining, CNC horizontal and vertical milling, CNC turning, multiple spindle drilling, polishing, stamping, light assembly and packaging.
2007年9月29日星期六
2007年9月26日星期三
Expendable Mold Technique
As its name implies, expendable mold casting makes use of expendable molds for the casting process. This does not imply the use of inexpensive materials, however; the process refers more to molds that have to be broken to remove the materials cast rather than 'throwaway,' single-use molds.
Among the most common (and oldest) examples of the expendable mold technique is sand casting. Sand casting makes use of a "molding box" - actually a container filled with sand (usually 'green' sand) in which the patterns of the piece to be cast are set.
Expendable casting uses a variety of materials for the mold - plaster, concrete, resins, even wax (in the so-called 'lost-wax' or investment casting technique). Recently, polystyrene foam has been used in expendable casting for complicated and complex parts such as automobile engines and the like.
Among the most common (and oldest) examples of the expendable mold technique is sand casting. Sand casting makes use of a "molding box" - actually a container filled with sand (usually 'green' sand) in which the patterns of the piece to be cast are set.
Expendable casting uses a variety of materials for the mold - plaster, concrete, resins, even wax (in the so-called 'lost-wax' or investment casting technique). Recently, polystyrene foam has been used in expendable casting for complicated and complex parts such as automobile engines and the like.
2007年9月24日星期一
Aluminum Casting Processes
Aluminum is one of the few metals that can be cast by all of the processes used in casting metals. These processes, in decreasing order of amount of aluminum casting, are: die casting, permanent mold casting, sand casting (green sand and dry sand), plaster casting, investment casting, and continuous casting. Other processes such as lost foam, squeeze casting, and hot isostatic pressing are also mentioned.
There are many factors that affect selection of a casting process for producing a specific aluminum alloy part. The most important factors for all casting processes are:
Feasibility and cost factors
Quality factors.
In terms of feasibility, many aluminum alloy castings can be produced by any of the available methods. For a considerable number of castings, however, dimensions or design features automatically determine the best casting method. Because metal molds weigh from 10 to 100 times as much as the castings they are used in producing, most very large cast products are made as sand castings rather than as die or permanent mold castings. Small castings usually are made with metal molds to ensure dimensional accuracy.
Quality factors are also important in the selection of a casting process. When applied to castings, the term quality refers to both degree of soundness (freedom from porosity, cracking, and surface imperfections) and levels of mechanical properties (strength and ductility).
However, it should be kept in mind that in die casting, although cooling rates are very high, air tends to be trapped in the casting, which gives rise to appreciable amounts of porosity at the center. Extensive research has been conducted to find ways of reducing such porosity; however, it is difficult if not impossible to eliminate completely, and die castings often are lower in strength than low-pressure or gravity-fed permanent mold castings, which are more sound in spite of slower cooling.
Die Casting
Alloys of aluminum are used in die casting more extensively than alloys of any other base metal. In the United States alone, about 2.5 billion dollars worth of aluminum alloy die castings is produced each year. The die casting process consumes almost twice as much tonnage of aluminum alloys as all other casting processes combined.
Die casting is especially suited to production of large quantities of relatively small parts. Aluminum die castings weighing up to about 5 kg are common, but castings weighing as much as 50 kg are produced when the high tooling and casting-machine costs are justified.
Typical applications of die cast aluminum alloys include:
Alloy 380.0 - Lawnmower housings, gear
Alloy A380.0 - Streetlamps housings, typewriter frames, dental equipment
Alloy 360.0 - Frying skillets, cover plates, instrument cases, parts requiring corrosion resistance.
Alloy 413.0 - Outboard motor parts such as pistons, connecting rods, and housings
Alloy 518.1 - Escalator parts, conveyor components, aircraft and marine hardware and lit tings.
With die casting, it is possible to maintain close tolerances and produce good surface finishes. Die castings are best designed with uniform wall thickness: minimum practical wall thickness for aluminum alloy die castings is dependent on casting size.
Die castings are made by injection of molten metal into metal molds under substantial pressure. Rapid injection and rapid solidification under high pressure combine to produce a dense, fine-grain surface structure, which results in excellent wear and fatigue properties. Air entrapment and shrinkage, however, may result in porosity, and machine cuts should be limited to 1.0 mm to avoid exposing it.
Aluminum alloy die castings usually are not heat treated but occasionally are given dimensional and metallurgical stabilization treatments.
Die castings are not easily welded or heat treated because of entrapped gases. Special techniques and care in production are required for pressure-tight parts. The selection of an alloy with a narrow freezing range also is helpful. The use of vacuum for cavity venting is practiced in some die casting foundries for production of parts for some special applications.
Approximately 85% of aluminum alloy die castings are produced in aluminum-silicon-copper alloys (alloy 380.0 and its several modifications). This family of alloys provides a good combination of cost, strength, and corrosion resistance, together with the high fluidity and freedom from hot shortness that are required for ease of casting. Where better corrosion resistance is required, alloys lower in copper, such as 360.0 and 413.0 must be used.
Alloy 518.0 is occasionally specified when highest corrosion resistance is required. This alloy, however, has low fluidity and some tendency to hot shortness. It is difficult to cast, which is reflected in higher cost per casting.
Permanent mold casting
Permanent mold (gravity die) casting, like die casting, is suited to high-volume production. Permanent mold castings typically are larger than die castings. Maximum weight of permanent mold castings usually is about 10 kg, but much larger castings sometimes are made when costs of tooling and casting equipment are justified by the quality required for the casting.
Permanent mold castings are gravity-fed and pouring rate is relatively low, but the metal mold produces rapid solidification. Permanent mold castings exhibit excellent mechanical properties. Castings are generally sound, provided that the alloys used exhibit good fluidity and resistance to hot tearing.
Mechanical properties of permanent mold castings can be further improved by heat treatment. If maximum properties are required, the heat treatment consists of a solution treatment at high temperature followed by a quench and then natural or artificial aging. For small castings in which the cooling rate in the mold is very rapid or for less critical parts, the solution treatment and quench may be eliminated and the fast cooling in the mold relied on to retain in solution the compounds that will produce age hardening.
Some common aluminum permanent mold casting alloys, and typical products cast from them, are presented below.
Alloy 366.0 - Automotive pistons
Alloys 355.0, C355.0, A357.0 - Timing gears, impellers, compressors, and aircraft and missile components requiring high strength
Alloys 356.0, A356.0 - Machine tool parts, aircraft wheels, pump parts, marine hardware, valve bodies
Other aluminum alloys commonly used for permanent mold castings include 296.0, 319.0, and 333.0.
Sand casting
Sand casting, which in a general sense involves the forming of a casting mold with sand, includes conventional sand casting and evaporative pattern (lost-foam) casting.
In conventional sand casting, the mold is formed around a pattern by ramming sand, mixed with the proper bonding agent, onto the pattern. Then the pattern is removed, leaving a cavity in the shape of the casting to be made. If the casting is to have internal cavities or undercuts, sand cores are used to make them. Molten metal is poured into the mold, and after it has solidified the mold is broken to remove the casting. In making molds and cores, various agents can be used for bonding the sand. The agent most often used is a mixture of clay and water.
Casting quality is determined to a large extent by foundry technique. Proper metal-handling practice is necessary for obtaining sound castings. Complex castings with varying wall thickness will be sound only if proper techniques are used.
Evaporative (lost-foam) pattern casting
Evaporative pattern casting (EPC) is a sand casting process that uses an unbounded sand mold with an expendable polystyrene pattern placed inside of the mold. This process is somewhat similar to investment casting in that an expendable material can be used to form relatively intricate patterns in a surrounding mold material. Unlike investment casting, however, evaporative pattern casting (EPC) involves a polystyrene foam pattern that vaporizes during the pouring of molten metal into a surrounding mold of unbounded sand.
Shell Mold Casting
In shell mold casting, the molten metal is poured into a shell of resin-bonded sand only 10 to 20 mm thick - much thinner than the massive molds commonly used in sand foundries. Shell mold castings surpass ordinary sand castings in surface finish and dimensional accuracy and cool at slightly higher rates; however, equipment and production are more expensive.
Plaster Casting
In this method, either a permeable (aerated) or impermeable plaster is used for the mold. The plaster in slurry form is poured around a pattern, the pattern is removed and the plaster mold is baked before the casting is poured. The high insulating value of the plaster allows castings with thin wads to be poured.
Minimum wall thickness of aluminum plaster castings typically is 1.5 mm. Plaster molds have high reproducibility, permitting castings to be made with fine details and close tolerances. Mechanical properties and casting quality depend on alloy composition and foundry technique. Slow cooling due to the highly insulating nature of plaster molds tends to magnify solidification-related problems, and thus solidification must be controlled carefully to obtain good mechanical properties.
Cost of basic equipment for plaster casting is low; however, because plaster molding is slower than sand molding, cost of operation is high. Aluminum alloys commonly used for plaster casting are 295.0, 355.0, C355.0, 356.0 and A356.0.
Investment casting
Investment casting of aluminum most commonly employs plaster molds and expendable patterns of wax or other fusible materials. Plaster slurry is "invested" around patterns for several castings, and the patterns are melted out as the plaster is baked.
Investment casting produces precision parts; aluminum castings can have walls as thin as 0.40 to 0.75 mm. However, investment molding is often used to produce large quantities of intricately shaped parts requiring no further machining so internal porosity seldom is a problem. Because of porosity and slow solidification, mechanical properties are low.
Investment castings usually are small, and it is especially suited to production of jewelry and parts for precision instruments. Recent strong interest by the aerospace industry in the investment casting process has resulted in limited use of improved technology to produce premium quality castings. Combining this accurate dimensional control with the high and carefully controlled mechanical properties can, at times, justify casting costs and prices normally not considered practical.
Aluminum alloys commonly used for investment castings are 208.0, 295.0, 308.0, 355.0, 356.0, 443,0, 514.0, 535.0 and 712.0.
Centrifugal Casting
Centrifuging is another method of forcing metal into a mold. Steel baked sand, plaster, cast iron, or graphite molds and cores are used for centrifugal casting of aluminum. Metal dies or molds provide rapid chilling, resulting in a level of soundness and mechanical properties comparable or superior to that of gravity-poured permanent mold castings.
Wheels, wheel hubs, and papermaking or printing rolls are examples of aluminum parts produced by centrifugal casting. Aluminum alloys suitable for permanent mold, sand, or plaster casting can be cast centrifugally.
Continuous Casting
Long shapes of simple cross section (such as round, square, and hexagonal rods) can be produced by continuous casting, which is done in a short, bottomless, water-cooled metal mold.
The casting is continuously withdrawn from the bottom of the mold; because the mold is water cooled, cooling rate is very high. As a result of continuous feeding, castings generally are free of porosity. In most instances, however, the same product can be made by extrusion at approximately the same cost and with better properties, and thus use of continuous casting is limited. The largest application of continuous casting is production of ingot for rolling, extrusion, or forging.
Composite-Mold Casting
Many of the molding methods described above can be combined to obtain greater flexibility in casting. Thus, dry sand cores often are used in green sand molds, and metal chills can be used in sand molds to accelerate local cooling.
Hot isostatic pressing
Hot isostatic pressing of aluminum castings reduces porosity and can thus decrease the scatter in mechanical properties. The method also makes possible the salvaging of castings that have been scrapped for reasons of internal porosity, thereby achieving improved foundry recovery. This advantage is of more significant importance in the manufacture of castings subject to radiographic inspection when required levels of soundness are not achieved in the casting process. The development of hot isostatic pressing is pertinent to the broad range of premium castings, but is especially relevant for the more difficult-to-cast aluminum-copper series.
Hybrid Permanent Mold Processes
Although die casting, centrifugal casting, and gravity die casting constitute, on a volume basis, the major permanent mold processes, there are also some hybrid processes that use permanent molds. This includes squeeze casting and semisolid metal processing.
The information from:http://www.key-to-metals.com/Article59.htm
There are many factors that affect selection of a casting process for producing a specific aluminum alloy part. The most important factors for all casting processes are:
Feasibility and cost factors
Quality factors.
In terms of feasibility, many aluminum alloy castings can be produced by any of the available methods. For a considerable number of castings, however, dimensions or design features automatically determine the best casting method. Because metal molds weigh from 10 to 100 times as much as the castings they are used in producing, most very large cast products are made as sand castings rather than as die or permanent mold castings. Small castings usually are made with metal molds to ensure dimensional accuracy.
Quality factors are also important in the selection of a casting process. When applied to castings, the term quality refers to both degree of soundness (freedom from porosity, cracking, and surface imperfections) and levels of mechanical properties (strength and ductility).
However, it should be kept in mind that in die casting, although cooling rates are very high, air tends to be trapped in the casting, which gives rise to appreciable amounts of porosity at the center. Extensive research has been conducted to find ways of reducing such porosity; however, it is difficult if not impossible to eliminate completely, and die castings often are lower in strength than low-pressure or gravity-fed permanent mold castings, which are more sound in spite of slower cooling.
Die Casting
Alloys of aluminum are used in die casting more extensively than alloys of any other base metal. In the United States alone, about 2.5 billion dollars worth of aluminum alloy die castings is produced each year. The die casting process consumes almost twice as much tonnage of aluminum alloys as all other casting processes combined.
Die casting is especially suited to production of large quantities of relatively small parts. Aluminum die castings weighing up to about 5 kg are common, but castings weighing as much as 50 kg are produced when the high tooling and casting-machine costs are justified.
Typical applications of die cast aluminum alloys include:
Alloy 380.0 - Lawnmower housings, gear
Alloy A380.0 - Streetlamps housings, typewriter frames, dental equipment
Alloy 360.0 - Frying skillets, cover plates, instrument cases, parts requiring corrosion resistance.
Alloy 413.0 - Outboard motor parts such as pistons, connecting rods, and housings
Alloy 518.1 - Escalator parts, conveyor components, aircraft and marine hardware and lit tings.
With die casting, it is possible to maintain close tolerances and produce good surface finishes. Die castings are best designed with uniform wall thickness: minimum practical wall thickness for aluminum alloy die castings is dependent on casting size.
Die castings are made by injection of molten metal into metal molds under substantial pressure. Rapid injection and rapid solidification under high pressure combine to produce a dense, fine-grain surface structure, which results in excellent wear and fatigue properties. Air entrapment and shrinkage, however, may result in porosity, and machine cuts should be limited to 1.0 mm to avoid exposing it.
Aluminum alloy die castings usually are not heat treated but occasionally are given dimensional and metallurgical stabilization treatments.
Die castings are not easily welded or heat treated because of entrapped gases. Special techniques and care in production are required for pressure-tight parts. The selection of an alloy with a narrow freezing range also is helpful. The use of vacuum for cavity venting is practiced in some die casting foundries for production of parts for some special applications.
Approximately 85% of aluminum alloy die castings are produced in aluminum-silicon-copper alloys (alloy 380.0 and its several modifications). This family of alloys provides a good combination of cost, strength, and corrosion resistance, together with the high fluidity and freedom from hot shortness that are required for ease of casting. Where better corrosion resistance is required, alloys lower in copper, such as 360.0 and 413.0 must be used.
Alloy 518.0 is occasionally specified when highest corrosion resistance is required. This alloy, however, has low fluidity and some tendency to hot shortness. It is difficult to cast, which is reflected in higher cost per casting.
Permanent mold casting
Permanent mold (gravity die) casting, like die casting, is suited to high-volume production. Permanent mold castings typically are larger than die castings. Maximum weight of permanent mold castings usually is about 10 kg, but much larger castings sometimes are made when costs of tooling and casting equipment are justified by the quality required for the casting.
Permanent mold castings are gravity-fed and pouring rate is relatively low, but the metal mold produces rapid solidification. Permanent mold castings exhibit excellent mechanical properties. Castings are generally sound, provided that the alloys used exhibit good fluidity and resistance to hot tearing.
Mechanical properties of permanent mold castings can be further improved by heat treatment. If maximum properties are required, the heat treatment consists of a solution treatment at high temperature followed by a quench and then natural or artificial aging. For small castings in which the cooling rate in the mold is very rapid or for less critical parts, the solution treatment and quench may be eliminated and the fast cooling in the mold relied on to retain in solution the compounds that will produce age hardening.
Some common aluminum permanent mold casting alloys, and typical products cast from them, are presented below.
Alloy 366.0 - Automotive pistons
Alloys 355.0, C355.0, A357.0 - Timing gears, impellers, compressors, and aircraft and missile components requiring high strength
Alloys 356.0, A356.0 - Machine tool parts, aircraft wheels, pump parts, marine hardware, valve bodies
Other aluminum alloys commonly used for permanent mold castings include 296.0, 319.0, and 333.0.
Sand casting
Sand casting, which in a general sense involves the forming of a casting mold with sand, includes conventional sand casting and evaporative pattern (lost-foam) casting.
In conventional sand casting, the mold is formed around a pattern by ramming sand, mixed with the proper bonding agent, onto the pattern. Then the pattern is removed, leaving a cavity in the shape of the casting to be made. If the casting is to have internal cavities or undercuts, sand cores are used to make them. Molten metal is poured into the mold, and after it has solidified the mold is broken to remove the casting. In making molds and cores, various agents can be used for bonding the sand. The agent most often used is a mixture of clay and water.
Casting quality is determined to a large extent by foundry technique. Proper metal-handling practice is necessary for obtaining sound castings. Complex castings with varying wall thickness will be sound only if proper techniques are used.
Evaporative (lost-foam) pattern casting
Evaporative pattern casting (EPC) is a sand casting process that uses an unbounded sand mold with an expendable polystyrene pattern placed inside of the mold. This process is somewhat similar to investment casting in that an expendable material can be used to form relatively intricate patterns in a surrounding mold material. Unlike investment casting, however, evaporative pattern casting (EPC) involves a polystyrene foam pattern that vaporizes during the pouring of molten metal into a surrounding mold of unbounded sand.
Shell Mold Casting
In shell mold casting, the molten metal is poured into a shell of resin-bonded sand only 10 to 20 mm thick - much thinner than the massive molds commonly used in sand foundries. Shell mold castings surpass ordinary sand castings in surface finish and dimensional accuracy and cool at slightly higher rates; however, equipment and production are more expensive.
Plaster Casting
In this method, either a permeable (aerated) or impermeable plaster is used for the mold. The plaster in slurry form is poured around a pattern, the pattern is removed and the plaster mold is baked before the casting is poured. The high insulating value of the plaster allows castings with thin wads to be poured.
Minimum wall thickness of aluminum plaster castings typically is 1.5 mm. Plaster molds have high reproducibility, permitting castings to be made with fine details and close tolerances. Mechanical properties and casting quality depend on alloy composition and foundry technique. Slow cooling due to the highly insulating nature of plaster molds tends to magnify solidification-related problems, and thus solidification must be controlled carefully to obtain good mechanical properties.
Cost of basic equipment for plaster casting is low; however, because plaster molding is slower than sand molding, cost of operation is high. Aluminum alloys commonly used for plaster casting are 295.0, 355.0, C355.0, 356.0 and A356.0.
Investment casting
Investment casting of aluminum most commonly employs plaster molds and expendable patterns of wax or other fusible materials. Plaster slurry is "invested" around patterns for several castings, and the patterns are melted out as the plaster is baked.
Investment casting produces precision parts; aluminum castings can have walls as thin as 0.40 to 0.75 mm. However, investment molding is often used to produce large quantities of intricately shaped parts requiring no further machining so internal porosity seldom is a problem. Because of porosity and slow solidification, mechanical properties are low.
Investment castings usually are small, and it is especially suited to production of jewelry and parts for precision instruments. Recent strong interest by the aerospace industry in the investment casting process has resulted in limited use of improved technology to produce premium quality castings. Combining this accurate dimensional control with the high and carefully controlled mechanical properties can, at times, justify casting costs and prices normally not considered practical.
Aluminum alloys commonly used for investment castings are 208.0, 295.0, 308.0, 355.0, 356.0, 443,0, 514.0, 535.0 and 712.0.
Centrifugal Casting
Centrifuging is another method of forcing metal into a mold. Steel baked sand, plaster, cast iron, or graphite molds and cores are used for centrifugal casting of aluminum. Metal dies or molds provide rapid chilling, resulting in a level of soundness and mechanical properties comparable or superior to that of gravity-poured permanent mold castings.
Wheels, wheel hubs, and papermaking or printing rolls are examples of aluminum parts produced by centrifugal casting. Aluminum alloys suitable for permanent mold, sand, or plaster casting can be cast centrifugally.
Continuous Casting
Long shapes of simple cross section (such as round, square, and hexagonal rods) can be produced by continuous casting, which is done in a short, bottomless, water-cooled metal mold.
The casting is continuously withdrawn from the bottom of the mold; because the mold is water cooled, cooling rate is very high. As a result of continuous feeding, castings generally are free of porosity. In most instances, however, the same product can be made by extrusion at approximately the same cost and with better properties, and thus use of continuous casting is limited. The largest application of continuous casting is production of ingot for rolling, extrusion, or forging.
Composite-Mold Casting
Many of the molding methods described above can be combined to obtain greater flexibility in casting. Thus, dry sand cores often are used in green sand molds, and metal chills can be used in sand molds to accelerate local cooling.
Hot isostatic pressing
Hot isostatic pressing of aluminum castings reduces porosity and can thus decrease the scatter in mechanical properties. The method also makes possible the salvaging of castings that have been scrapped for reasons of internal porosity, thereby achieving improved foundry recovery. This advantage is of more significant importance in the manufacture of castings subject to radiographic inspection when required levels of soundness are not achieved in the casting process. The development of hot isostatic pressing is pertinent to the broad range of premium castings, but is especially relevant for the more difficult-to-cast aluminum-copper series.
Hybrid Permanent Mold Processes
Although die casting, centrifugal casting, and gravity die casting constitute, on a volume basis, the major permanent mold processes, there are also some hybrid processes that use permanent molds. This includes squeeze casting and semisolid metal processing.
The information from:http://www.key-to-metals.com/Article59.htm
2007年9月22日星期六
Die-casting Machine
die casting ,aluminium die casting,pressure die casting factory have Large spectrum of die casting machines (280T - 1600T),it can produce Variety of alloys available to meet in house production requirements and to provide quality custom-made die-casting parts for other industries
Factory Equipment
if you want to more about casting machine,please vistied www.nbdiecasting.com
Factory Equipment
if you want to more about casting machine,please vistied www.nbdiecasting.com
2007年9月19日星期三
GGB to Begin Production in China
GGB, formerly Glacier Garlock Bearings, today announced plans to begin manufacturing in China later this year.
¡°Our new production facility in China will provide a local source of world-class, high-performance bearings both for existing customers that have operations there, as well as the indigenous Chinese market, explained Joseph Fults, GGB vice president, Asia and business development.
GGB will occupy a 4,000-square-meter facility in Suzhou, approximately a two-hour drive west of Shanghai, which is being built out to current Western standards. Scheduled for completion in the fourth quarter of this year, the new plant will initially employ 25 people and produce all of GGB¡¯s metal-polymer and filament-wound bearings.
In 2004 GGB opened a sales office in Shanghai which has since been expanded, and opened a second office in Beijing earlier this year.Auto Bearings,automotive bearings,automobile bearings,industrial bearings,Ball Bearings,Miniature Ball Bearings ,Wheel Bearings
http://www.hiana-bearings.com/bearings_news/GGB_in_china.htm
Aluminum die Casting
Aluminium die casting,aluminum die casting process is always used for heavy part with big wall thickness and very strong mechanical property after T6 heat treatment. Its also better to avoid porosity inside casting after secondary machining. Gravity casting part is nice looking with better surface than sand casting, but sand casting is more flexibility even it is very complicated shape. 356 T6 is the most common raw material.
2007年9月16日星期日
Casting call for NBC talent contest
NBC announced a casting call for the grammatically stunning America's Got Talent, the latest in Simon Cowell's plan for world domination (is he more over-exposed than Ryan Seacrest or what?). Judging from the vague information provided in the press release, the talent competition may very well be a rip-off of Star Search. People in various age groups and talent categories will compete for fame and fortune. It will air this summer on NBC.
Casting begins on April 6 in Los Angeles. Producers are looking for singers, dancers, comedians, and unique stage acts (Letterman's 'Grinder Girl' comes to mind). Click here for casting call dates and locations.
Casting begins on April 6 in Los Angeles. Producers are looking for singers, dancers, comedians, and unique stage acts (Letterman's 'Grinder Girl' comes to mind). Click here for casting call dates and locations.
2007年9月12日星期三
CWM CEO Leads IMA to 1st China Conference
In pursuit of the goal of the International Magnesium Assn. to promote wider worldwide use of magnesium, the IMA held its first Annual World Magnesium Conference in Beijing, China, jointly organized by the China Magnesium Assn. Walter Treiber, CWM CEO, led this international industry conclave of lectures and exhibits as the IMA’s president. Aluminum Lost Wax Casting,Aluminum Gravity Casting,Aluminum Precision Casting,Aluminum Alloy Casting,Aluminum Investment Casting,Aluminum Die Casting,Pressure Die Casting,aluminum casting,aluminum sand casting,Sand Casting,Investment casting
Building the Die Cast Mg Market A major feature of the Conference was the presentation of IMA awards for excellence in magnesium die casting and display of past award-winning examples. CWM has won this award, which promotes new die casting applications, many times in the past.
Die Casting Now Leads All Mg Usage Among the magnesium end-use categories, die casting is now estimated to be the single largest usage category in 2005, and appears on track for continued growth in both the automotive and non-automotive markets.
Magnesium die casting is growing at nearly twice the rate of overall Mg consumption, according to data from the IMA. Aluminium Alloy Casting Stainless Steel Casting Corrosion Resistant Steel Casting Alloy Steel Casting Refractory Steel Casting Carbon Steel Casting , Die casting Lighting industry, Die casting Motorcycle Parts, Aluminum Lost Wax Casting, Aluminum Pressure Die Casting, Die Castings, Pressure Die Castings, Aluminum Die Casting, Aluminum Alloy Casting, Aluminum Investment Casting, Investment casting, Precision CNC Machining, Precision CNC Machining Components, Zinc Die Casting, green sand casting,
Building the Die Cast Mg Market A major feature of the Conference was the presentation of IMA awards for excellence in magnesium die casting and display of past award-winning examples. CWM has won this award, which promotes new die casting applications, many times in the past.
Die Casting Now Leads All Mg Usage Among the magnesium end-use categories, die casting is now estimated to be the single largest usage category in 2005, and appears on track for continued growth in both the automotive and non-automotive markets.
Magnesium die casting is growing at nearly twice the rate of overall Mg consumption, according to data from the IMA. Aluminium Alloy Casting Stainless Steel Casting Corrosion Resistant Steel Casting Alloy Steel Casting Refractory Steel Casting Carbon Steel Casting , Die casting Lighting industry, Die casting Motorcycle Parts, Aluminum Lost Wax Casting, Aluminum Pressure Die Casting, Die Castings, Pressure Die Castings, Aluminum Die Casting, Aluminum Alloy Casting, Aluminum Investment Casting, Investment casting, Precision CNC Machining, Precision CNC Machining Components, Zinc Die Casting, green sand casting,
CWM EPA Report: Chemical Usage Down
As a charter member of the U.S. EPA’s National Environmental Performance Track program, CWM submitted its annual report detailing the progress the company has made in its ongoing commitments to environmental initiatives. The long-term goal of the program is to enable strategies leading to significant reductions in pollution, waste, environmental and human health impacts, with a decrease in regulatory burdens. The CWM report to the Performance Track program included:
Reductions in Chemical and Process Water Usage
Reductions of 21% in the amount of die casting die lubricant used in the aluminum die casting department and of 50% in the amount of SF6 gas used in the magnesium die casting department, despite increased production in both departments; Elimination of approximately 4,000 lbs. per year of chemicals used to treat process water through the installation of a new environmentally friendly process water system; Reduction by 22% in the amount of process water used company wide.
Materials Recycling Activity
Recycling of 9,300 lbs. of magnesium machining chips through processing into small, solid blocks used for desulfurization in steel production; Recycling of 10,000 lbs. of office paper, 12,000 lbs. of corrugated materials, 1,000 lbs. of plastic stretch film, 71,000 lbs. of steel, and 445 wood pallets.
Chicago White Metal was the first die caster to achieve ISO 14001 registration for its environmental management system and has served as a mentor facility for the EPA to the die casting industry. Die casting Lighting industry, Die casting Motorcycle Parts, Aluminum Lost Wax Casting, Aluminum Pressure Die Casting, Die Castings, Pressure Die Castings, Aluminum Die Casting, Aluminum Alloy Casting, Aluminum Investment Casting, Investment casting, Precision CNC Machining, Precision CNC Machining Components, Zinc Die Casting, green sand casting
Reductions in Chemical and Process Water Usage
Reductions of 21% in the amount of die casting die lubricant used in the aluminum die casting department and of 50% in the amount of SF6 gas used in the magnesium die casting department, despite increased production in both departments; Elimination of approximately 4,000 lbs. per year of chemicals used to treat process water through the installation of a new environmentally friendly process water system; Reduction by 22% in the amount of process water used company wide.
Materials Recycling Activity
Recycling of 9,300 lbs. of magnesium machining chips through processing into small, solid blocks used for desulfurization in steel production; Recycling of 10,000 lbs. of office paper, 12,000 lbs. of corrugated materials, 1,000 lbs. of plastic stretch film, 71,000 lbs. of steel, and 445 wood pallets.
Chicago White Metal was the first die caster to achieve ISO 14001 registration for its environmental management system and has served as a mentor facility for the EPA to the die casting industry. Die casting Lighting industry, Die casting Motorcycle Parts, Aluminum Lost Wax Casting, Aluminum Pressure Die Casting, Die Castings, Pressure Die Castings, Aluminum Die Casting, Aluminum Alloy Casting, Aluminum Investment Casting, Investment casting, Precision CNC Machining, Precision CNC Machining Components, Zinc Die Casting, green sand casting
2007年9月9日星期日
Aluminium alloy
Aluminium alloys or aluminum alloys are alloys of aluminium, often with copper, zinc, manganese, silicon, or magnesium. They are much lighter and more corrosion resistant than plain carbon steel, but not quite as corrosion resistant as pure aluminium. Bare aluminium alloy surfaces will keep their apparent shine in a dry environment, but light amounts of corrosion products rub off easily onto skin when touched. Galvanic corrosion can be rapid when aluminium alloy is placed in proximity to stainless steel in a wet environment. Aluminium alloy and stainless steel parts should not be mixed in water-containing systems or outdoor installations.
Aluminium alloy compositions are registered with the Aluminium Association. Many organizations publish more specific standards for the manufacture of aluminium alloy, including the Society of Automotive Engineers standards organization, specifically its aerospace standards subgroups
Aluminium alloy compositions are registered with the Aluminium Association. Many organizations publish more specific standards for the manufacture of aluminium alloy, including the Society of Automotive Engineers standards organization, specifically its aerospace standards subgroups
2007年9月6日星期四
What is Casting
Casting is a mass production process which involves molten materials (such as metals, plastics or resins) being poured into a mold, allowed to solidify and then extracted for use. Casting can be thought of as a method for reproducing something - whether a mere part or a single unit by itself.
Casting is a process that can be used to manufacture complex parts which would prove too expensive or time-consuming to produce using other methods such as cutting or shaping these from solid materials.
Non-expendable Casting Techniques
This involves the use of more or less permanent or long-lasting molds which do not need to be broken in order to remove the cast material once it has set or cooled. Die casting is probably the most well-known non-expendable casting process known, in which molten metal or other material is forced, under high pressure, into the cavities of steel molds called dies.
The die casting method is straightforward. The die or mold is fabricated (containing the impressions of the piece to be cast). A lubricant is sprayed on the inside of the die both to cool it off as well as assist in making removal of the cast piece easy. Once the whole thing is set up, molten material is 'injected' into the die under high speed and high pressure, this helps a lot in making a casting as smooth and as precise as the original mold. Once the cavity is filled with the desired material, pressure is maintained until the material has cooled (which is helped along by using water to cool the mold). Once the material has cooled and hardened, the die is opened and the material ejected to pave the way for the next casting.
The major advantage of die casting is the ability to use the mold or die repeatedly and continuously - although even the die will deteriorate due to the high-pressure and high-speed injection of molten material (usually nonferrous metals like zinc or aluminum or plastics). At the same time, the mold can be used to replicate intricate and complex patterns ranging from small to large pieces which make it the process of choice for the manufacturing of certain items.
Expendable Mold Technique
As its name implies, expendable mold casting makes use of expendable molds for the casting process. This does not imply the use of inexpensive materials, however; the process refers more to molds that have to be broken to remove the materials cast rather than 'throwaway,' single-use molds.
Among the most common (and oldest) examples of the expendable mold technique is sand casting. Sand casting makes use of a "molding box" - actually a container filled with sand (usually 'green' sand) in which the patterns of the piece to be cast are set.
Expendable casting uses a variety of materials for the mold - plaster, concrete, resins, even wax (in the so-called 'lost-wax' or investment casting technique). Recently, polystyrene foam has been used in expendable casting for complicated and complex parts such as automobile engines and the like.
Casting is a process that can be used to manufacture complex parts which would prove too expensive or time-consuming to produce using other methods such as cutting or shaping these from solid materials.
Non-expendable Casting Techniques
This involves the use of more or less permanent or long-lasting molds which do not need to be broken in order to remove the cast material once it has set or cooled. Die casting is probably the most well-known non-expendable casting process known, in which molten metal or other material is forced, under high pressure, into the cavities of steel molds called dies.
The die casting method is straightforward. The die or mold is fabricated (containing the impressions of the piece to be cast). A lubricant is sprayed on the inside of the die both to cool it off as well as assist in making removal of the cast piece easy. Once the whole thing is set up, molten material is 'injected' into the die under high speed and high pressure, this helps a lot in making a casting as smooth and as precise as the original mold. Once the cavity is filled with the desired material, pressure is maintained until the material has cooled (which is helped along by using water to cool the mold). Once the material has cooled and hardened, the die is opened and the material ejected to pave the way for the next casting.
The major advantage of die casting is the ability to use the mold or die repeatedly and continuously - although even the die will deteriorate due to the high-pressure and high-speed injection of molten material (usually nonferrous metals like zinc or aluminum or plastics). At the same time, the mold can be used to replicate intricate and complex patterns ranging from small to large pieces which make it the process of choice for the manufacturing of certain items.
Expendable Mold Technique
As its name implies, expendable mold casting makes use of expendable molds for the casting process. This does not imply the use of inexpensive materials, however; the process refers more to molds that have to be broken to remove the materials cast rather than 'throwaway,' single-use molds.
Among the most common (and oldest) examples of the expendable mold technique is sand casting. Sand casting makes use of a "molding box" - actually a container filled with sand (usually 'green' sand) in which the patterns of the piece to be cast are set.
Expendable casting uses a variety of materials for the mold - plaster, concrete, resins, even wax (in the so-called 'lost-wax' or investment casting technique). Recently, polystyrene foam has been used in expendable casting for complicated and complex parts such as automobile engines and the like.
casting Process
Investment casting also can be called "precise casting" or " lost wax casting" or "dewaxing casting". the casting materials can widely used, and no limitation for product shape as well as complex structure. The most important characteristic is the close tolerances control, reduced machining allowances, and fine surface finish. Its application scope can be wider after using the new equipment and advanced technology. In heat processing industry, investment casting can be used for those products which difficult to choice the materials, or materials not easy to form a shape, as well as some forging pieces with higher cost; while in the casting industry, the investment casting can be used instead of other casting methods, so as to reduce machining allowances and the cost, improve the dimensional precision and surface finish as well as the mechanical properties, so as to meet the requirements of a higher level product.
Further information, please don't hesitate to contact with us, we will give you the most satisfied reply.
We undertake the processing cooperation for drawings and samples at home, even all over the world, if you need to inquire about price, please submit the related information, we will offer you a most favorable price as soon as possible. die casting,casting,aluminium die casting,aluminum casting,sand casting,iron sand casting,investment casting,pressure die casting ,gear housing,Quick Coupling Series
,Precision CNC Machining Components ,Valve Balls and Valve Industry,Pressure Die Casting,aluminum die casting,Investment Casting,Sand casting,Iron casting,CNC machining,alloy die casting,zinc die casting,low pressure die casting,aluminum pressure die casting,die casting machine,lost wax casting,Pressure Die Casting,aluminum die casting,Investment Casting,Sand casting,Iron casting,CNC machining,alloy die casting,zinc die casting,low pressure die casting,aluminum pressure die casting,die casting machine,lost wax casting,high pressure die casting,permanent mold casting,stainless steel casting,aluminum casting foundry,green sand casting,aluminum investment casting,iron casting,aluminum lost wax casting,die casting for lighting industry,die casting Motorcycle Parts
Mature technological process, rich experience, professional large scale production, effective cost management made us possess the strong comprehensive competitive capability better than other manufactory in this vocation, all these not only show in our high quality, the most attractive price also is our treasure book.
If you come from America or Europe, please trust us, because of the lowest productive cost in China, so, purchasing casting in China is your best choice. Don't hesitate, our offer will make you a big surprise.
Further information, please don't hesitate to contact with us, we will give you the most satisfied reply.
We undertake the processing cooperation for drawings and samples at home, even all over the world, if you need to inquire about price, please submit the related information, we will offer you a most favorable price as soon as possible. die casting,casting,aluminium die casting,aluminum casting,sand casting,iron sand casting,investment casting,pressure die casting ,gear housing,Quick Coupling Series
,Precision CNC Machining Components ,Valve Balls and Valve Industry,Pressure Die Casting,aluminum die casting,Investment Casting,Sand casting,Iron casting,CNC machining,alloy die casting,zinc die casting,low pressure die casting,aluminum pressure die casting,die casting machine,lost wax casting,Pressure Die Casting,aluminum die casting,Investment Casting,Sand casting,Iron casting,CNC machining,alloy die casting,zinc die casting,low pressure die casting,aluminum pressure die casting,die casting machine,lost wax casting,high pressure die casting,permanent mold casting,stainless steel casting,aluminum casting foundry,green sand casting,aluminum investment casting,iron casting,aluminum lost wax casting,die casting for lighting industry,die casting Motorcycle Parts
Mature technological process, rich experience, professional large scale production, effective cost management made us possess the strong comprehensive competitive capability better than other manufactory in this vocation, all these not only show in our high quality, the most attractive price also is our treasure book.
If you come from America or Europe, please trust us, because of the lowest productive cost in China, so, purchasing casting in China is your best choice. Don't hesitate, our offer will make you a big surprise.
2007年9月4日星期二
Cast iron
Iron (Fe) accounts for more than 95% of the alloy material, while the main alloying elements are carbon (C) and silicon (Si). The amount of carbon in cast irons is 2.1 - 4%, while ferrous alloys with less carbon are denoted as carbon steel by definition. Cast irons contain appreciable amounts of silicon, normally 1 - 3%, and consequently these alloys should be considered ternary Fe-C-Si alloys.
Despite this, the principles of cast iron solidification are understood from the binary iron-carbon phase diagram, where the eutectic point lies at 1154 °C and 4.3 wt% carbon. Since cast iron has nearly this composition, its melting temperature of 1150 to 1200 °C is about 300 degrees lower than the melting point of pure iron. Cast iron tends to be brittle, unless the name of the particular alloy suggests otherwise. The color of a fracture surface can be used to identify an alloy: carbide impurities allow cracks to pass straight through, resulting in a smooth, "white" surface, while graphite flakes deflect a passing crack and initiate countless new cracks as the material breaks, resulting in a rough surface that appears grey.
With its low melting point, good fluidity, castability, excellent machinability and wear resistance, cast irons have become an engineering material with a wide range of applications, including pipes, machine and car parts.
Despite this, the principles of cast iron solidification are understood from the binary iron-carbon phase diagram, where the eutectic point lies at 1154 °C and 4.3 wt% carbon. Since cast iron has nearly this composition, its melting temperature of 1150 to 1200 °C is about 300 degrees lower than the melting point of pure iron. Cast iron tends to be brittle, unless the name of the particular alloy suggests otherwise. The color of a fracture surface can be used to identify an alloy: carbide impurities allow cracks to pass straight through, resulting in a smooth, "white" surface, while graphite flakes deflect a passing crack and initiate countless new cracks as the material breaks, resulting in a rough surface that appears grey.
With its low melting point, good fluidity, castability, excellent machinability and wear resistance, cast irons have become an engineering material with a wide range of applications, including pipes, machine and car parts.
Coffee Pot
Zhongjiang Company is a professional manufacturer specialized in producing Stainless Steel Daily-use products; the company not only has technical talents, but also an experienced administration and management team; it possesses the advanced production equipments and the technical team of high efficiency production; it adopts and enjoys the outstanding manufacturing technology and process; it gives an accurate control on every manufacturing process and carry out the production in line with the international standards; the Main Products include:
1. Stainless Steel Coffee Utensils: Coffeepot, Coffee Spoon£»
2. Hotel Utensils: Order Holder, Chopsticks Holder, Measuring Cup, Stainless Soap.
3. Kitchen Utensils: Pot, Soup Spoon, Frying Shovel, Special Spoon, Strainer spoon, Strainer Basket;
The products are in a complete range of specifications, a fashionable design and reliable quality; Zhongjiang Products are mainly exported to some regions and countries like Asia, USA and Europe.
Zhongjiang Company, adhering to Quality Foremost, Credit Fundamental and Customer First, will provide and offer its first class products and service to worldwide customers.
Coffee pot
Material:18/8 304 from Korea
Thinkness:0.8mm
MIRROR-POLISHING TREATMENT
Size:1.9L
Qty/Ctn:12pcs
Carton meas:48*44*34.5cm
G.W/N.W(kgs):10/7
from:http://coffeeware.blogspot.com/
1. Stainless Steel Coffee Utensils: Coffeepot, Coffee Spoon£»
2. Hotel Utensils: Order Holder, Chopsticks Holder, Measuring Cup, Stainless Soap.
3. Kitchen Utensils: Pot, Soup Spoon, Frying Shovel, Special Spoon, Strainer spoon, Strainer Basket;
The products are in a complete range of specifications, a fashionable design and reliable quality; Zhongjiang Products are mainly exported to some regions and countries like Asia, USA and Europe.
Zhongjiang Company, adhering to Quality Foremost, Credit Fundamental and Customer First, will provide and offer its first class products and service to worldwide customers.
Coffee pot
Material:18/8 304 from Korea
Thinkness:0.8mm
MIRROR-POLISHING TREATMENT
Size:1.9L
Qty/Ctn:12pcs
Carton meas:48*44*34.5cm
G.W/N.W(kgs):10/7
from:http://coffeeware.blogspot.com/
2007年9月2日星期日
stainless steel casting
consisting mostly of iron, with a carbon content between 0.02% and 1.7 or 2.04% by weight (C:1000–10,8.67Fe), depending on grade. Carbon is the most cost-effective alloying material for iron, but various other alloying elements are used such as manganese and tungsten.[1] Carbon and other elements act as a hardening agent, preventing dislocations in the iron atom crystal lattice from sliding past one another. Varying the amount of alloying elements and form of their presence in the steel (solute elements, precipitated phase) controls qualities such as the hardness, ductility, and tensile strength of the resulting steel. Steel with increased carbon content can be made harder and stronger than iron, but is also more brittle. The maximum solubility of carbon in iron (in austenite region) is 2.14% by weight, occurring at 1149 °C; higher concentrations of carbon or lower temperatures will produce cementite. Alloys with higher carbon content than this are known as cast iron because of their lower melting point.[1] Steel is also to be distinguished from wrought iron containing only a very small amount of other elements, but containing 1–3% by weight of slag in the form of particles elongated in one direction, giving the iron a characteristic grain. It is more rust-resistant than steel and welds more easily. But at present time this term is rarely used in steel industry. It is common today to talk about 'the iron and steel industry' as if it were a single entity, but historically they were separate products.
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permanent mold casting
Permanent mold castings, while not as flexible as sand castings in allowing the use of different patterns (different part designs), lower the cost of producing a part. At a production run of 1000 or more parts, permanent mold castings produce a lower piece cost part. Of course, the break-even point depends on the complexity of the part. More complex parts being favored by the use of permanent molds.
The usual considerations of minimum wall thicknesses (such as 3mm for lengths under 75 mm), radius (inside radius = nominal wall thickness, outside radius = 3 x nominal wall thickness), draft angles (1 to 3?on outside surfaces, 2 to 5on inside surfaces) etc all apply. Typical tolerances are 2 % of linear dimensions. .
Typical part sizes range from 50 g to 70 kg (1.5 ounces to 150 lb). Typical materials used are small and medium sized parts made from aluminum, magnesium and brass and their alloys. Typical parts include gears, splines, wheels, gear housings, pipefittings, fuel injection housings, and automotive engine pistons.
Other Permanent Mold Castings
Slush Casting: Slush Casting is a special type of permanent mold casting, where the molten metal is not allowed to completely solidify. After the desired wall thickness is obtained, the not yet solidified molten metal is poured out. This is useful for making hollow ornamental objects such as candlesticks, lamps, statues etc.
Corthias Casting: Corthias Casting is another variation of the permanent mold casting, where a plunger is used to pack down the molten metal form the sprue hole. This allows for thinner walls and greater details to be produced.
Low Pressure Permanent Mold Casting: Low Pressure Permanent Mold Casting is yet another variation of the permanent mold casting. Here, instead of using gravity to assist in the metal pour and flow in the mold, a low pressure of upto 1 atmosphere gas is applied to the molten metal. This maintenance of pressure on the melt causes complete fill of the mold and compensates for any shrinkage on cooling. Thin wall castings can be made. Mechanical properties are about 5 % superior to permanent mold casting. Since no riser is used (unlike a regular casting), the yield is generally higher since the metal in the pressurized feed tube is still molten and the mold is ready for the next shot right away.
Vacuum Permanent Mold Casting
Vacuum Permanent Mold Casting is yet another variation of the permanent mold casting. This is similar to the low-pressure permanent mold casting, where a vacuum is used instead of a pressure. Thin wall castings can be made as in the low-pressure permanent mold casting. In addition, the yields are high since no risers are used. Since vacuum is used instead, the purity of the metal is maintained. The mechanical properties of the casting are 10 to 15 % superior to the traditional permanent mold casting. Castings range in size from 200 g to 4.5 kg (6 oz to 10 lb).
The usual considerations of minimum wall thicknesses (such as 3mm for lengths under 75 mm), radius (inside radius = nominal wall thickness, outside radius = 3 x nominal wall thickness), draft angles (1 to 3?on outside surfaces, 2 to 5on inside surfaces) etc all apply. Typical tolerances are 2 % of linear dimensions. .
Typical part sizes range from 50 g to 70 kg (1.5 ounces to 150 lb). Typical materials used are small and medium sized parts made from aluminum, magnesium and brass and their alloys. Typical parts include gears, splines, wheels, gear housings, pipefittings, fuel injection housings, and automotive engine pistons.
Other Permanent Mold Castings
Slush Casting: Slush Casting is a special type of permanent mold casting, where the molten metal is not allowed to completely solidify. After the desired wall thickness is obtained, the not yet solidified molten metal is poured out. This is useful for making hollow ornamental objects such as candlesticks, lamps, statues etc.
Corthias Casting: Corthias Casting is another variation of the permanent mold casting, where a plunger is used to pack down the molten metal form the sprue hole. This allows for thinner walls and greater details to be produced.
Low Pressure Permanent Mold Casting: Low Pressure Permanent Mold Casting is yet another variation of the permanent mold casting. Here, instead of using gravity to assist in the metal pour and flow in the mold, a low pressure of upto 1 atmosphere gas is applied to the molten metal. This maintenance of pressure on the melt causes complete fill of the mold and compensates for any shrinkage on cooling. Thin wall castings can be made. Mechanical properties are about 5 % superior to permanent mold casting. Since no riser is used (unlike a regular casting), the yield is generally higher since the metal in the pressurized feed tube is still molten and the mold is ready for the next shot right away.
Vacuum Permanent Mold Casting
Vacuum Permanent Mold Casting is yet another variation of the permanent mold casting. This is similar to the low-pressure permanent mold casting, where a vacuum is used instead of a pressure. Thin wall castings can be made as in the low-pressure permanent mold casting. In addition, the yields are high since no risers are used. Since vacuum is used instead, the purity of the metal is maintained. The mechanical properties of the casting are 10 to 15 % superior to the traditional permanent mold casting. Castings range in size from 200 g to 4.5 kg (6 oz to 10 lb).
Lost-wax casting
1. Sculpting. An artist creates an original artwork from wax, clay, or another material. Wax and oil-based clay are often preferred because these materials retain their softness.
2. Moldmaking. A mold is made of the original sculpture. Most molds are at least two pieces, and a shim with keys is placed between the two halves during construction so that the mold can be put back together accurately. Most molds of small sculptures are made from plaster, but can also be made of fiberglass or other materials. To preserve the fine details on the original artwork's surface, there is usually an inner mold made of latex, vinyl, or silicone which is supported by the plaster part of the mold. Usually, the original artwork is destroyed during the making and initial deconstruction of the plaster mold. This is because the originals are solid, and do not easily bend as the plaster mold is removed. Often long, thin pieces are cut off of the original and molded separately. Sometimes, especially in the case of large original (such as life-size) sculptures, many molds are needed to recreate the original sculpture.
3. Wax. Once the plaster and latex mold is finished, molten wax is poured into it and swished around until an even coating, usually about 1/8 inches thick, covers the entire inner surface of the mold. This must be done in several layers until desired thickness is reached.
4. Removal of wax. This new, hollow wax copy of the original artwork is removed from the mold. The artist may reuse the mold to make more wax copies, but wear and tear on the mold limit their number. For small bronze artworks, a common number of copies today is around 25.
5. Chasing. Each hollow wax copy is then "chased": a heated metal tool is used to rub out all the marks which show the "parting line" or "flashing" where the pieces of the mold came together. The wax is then "dressed" to hide any imperfections. The way the wax looks at this stage, is what it will look like when it is cast. Wax pieces that were molded separately can be heated and attached; foundries often use "registration marks" to indicate exactly where they go.
6. Spruing. Once the wax copy looks just like the original artwork, it is "sprued" with a treelike structure of wax that will eventually provide paths for molten bronze to flow, while allowing air to escape. The carefully-planned spruing usually begins at the top with a wax "cup," which is attached by wax cylinders to various points on the wax copy.
7. Slurry. A "sprued" wax copy is dipped into a slurry of liquid silica, then into a sand-like "stucco", or dry crystalline silica of a controlled grain size. The slurry and grit combination is called "ceramic shell" mold material, although it is not literally made of ceramic. This shell is allowed to dry, and the process is repeated until a half-inch thick or thicker dries coating covers the entire piece. The bigger the piece, the thicker the shell needs to be. Only the inside of the cup is not coated, and the cup's flat top serves as the base upon which the piece stands during this process.
8. Burnout. The ceramic shell-coated piece is placed cup-down in a kiln, whose heat hardens the silica coatings into a shell, and the wax melts and runs out. The melted wax can be recovered and reused, although often it is simply combusted by the burnout process. Now all that remains of the original artwork is the negative space, formerly occupied by the wax, inside the hardened ceramic shell. The feeder and vent tubes and cup are now hollow, also.
9. Testing. The ceramic shell is allowed to cool, then is tested to see if water will flow through the feeder and vent tubes as necessary. Cracks or leaks can be patched with thick refractory paste. To test the thickness, holes can be drilled into the shell, then patched.
10. Pouring. The shell is reheated in the kiln to harden the patches, then placed cup-upwards into a tub filled with sand. Bronze is melted in a crucible in a furnace, then poured carefully into the shell. If the shell were not hot, the temperature difference would shatter it. The bronze-filled shells are allowed to cool.
11. Release.The shell is hammered or sand-blasted away, releasing the rough bronze. The spruing, which are also faithfully recreated in metal, are cut off, to be reused in another casting.
12. Metal-chasing. Just as the wax copies were "chased," the bronze copies are worked until the telltale signs of casting are removed, and the sculptures again look like the original artwork. Pits left by air bubbles in the molten bronze are filled, and the stubs of spruing filed down and polished.
13. Patinating. The bronze is colored to the artist's preference, using chemicals applied to heated or cooled metal. Using heat is probably the most predicatable method, and allows the artist to have the most control over the process. This coloring is called patina, and is often green, black, white or brownish to simulate the surfaces of ancient bronze sculptures. (Ancient bronzes gained their patinas from oxidisation and other effects of being on Earth for many years.) However, with current artistic trends in the United States, many artists prefer that their bronzes have brighter, more stylized patinas. Patinas can be applied to replicate marble or stone. Depending on how the metal is prepared, either sandblasted or polished, the finish can be either opaque or transparent. After the patina is applied, a coating of wax, which is the most traditional type of sealer, is usually applied to protect the surface. Many artists prefer to use lacquer as a sealer on some of the more unstable patinas. This protects the piece more from ultraviolet rays. Some patinas change color over time because of oxidiation, and the wax layer slows this down somewhat.
On the left is an example of a lost-wax process mold, and on the right is the resulting bronze sculpture.
On the left is an example of a lost-wax process mold, and on the right is the resulting bronze sculpture.
The lost-wax process can also be used with any material that can burn, melt, or evaporate to leave a mold cavity. Some automobile manufacturers use a lost-foam technique to make engine blocks. The model in this case is made of polystyrene foam, which is then placed into a casting flask, consisting of a cope and drag, which is then filled with casting sand. The foam supports the sand, allowing shapes to be made which would not be possible if the process had to rely on the sand alone to hold its shape. The metal is then poured in, and the heat of the metal vaporizes the foam as the metal enters the mold.
2. Moldmaking. A mold is made of the original sculpture. Most molds are at least two pieces, and a shim with keys is placed between the two halves during construction so that the mold can be put back together accurately. Most molds of small sculptures are made from plaster, but can also be made of fiberglass or other materials. To preserve the fine details on the original artwork's surface, there is usually an inner mold made of latex, vinyl, or silicone which is supported by the plaster part of the mold. Usually, the original artwork is destroyed during the making and initial deconstruction of the plaster mold. This is because the originals are solid, and do not easily bend as the plaster mold is removed. Often long, thin pieces are cut off of the original and molded separately. Sometimes, especially in the case of large original (such as life-size) sculptures, many molds are needed to recreate the original sculpture.
3. Wax. Once the plaster and latex mold is finished, molten wax is poured into it and swished around until an even coating, usually about 1/8 inches thick, covers the entire inner surface of the mold. This must be done in several layers until desired thickness is reached.
4. Removal of wax. This new, hollow wax copy of the original artwork is removed from the mold. The artist may reuse the mold to make more wax copies, but wear and tear on the mold limit their number. For small bronze artworks, a common number of copies today is around 25.
5. Chasing. Each hollow wax copy is then "chased": a heated metal tool is used to rub out all the marks which show the "parting line" or "flashing" where the pieces of the mold came together. The wax is then "dressed" to hide any imperfections. The way the wax looks at this stage, is what it will look like when it is cast. Wax pieces that were molded separately can be heated and attached; foundries often use "registration marks" to indicate exactly where they go.
6. Spruing. Once the wax copy looks just like the original artwork, it is "sprued" with a treelike structure of wax that will eventually provide paths for molten bronze to flow, while allowing air to escape. The carefully-planned spruing usually begins at the top with a wax "cup," which is attached by wax cylinders to various points on the wax copy.
7. Slurry. A "sprued" wax copy is dipped into a slurry of liquid silica, then into a sand-like "stucco", or dry crystalline silica of a controlled grain size. The slurry and grit combination is called "ceramic shell" mold material, although it is not literally made of ceramic. This shell is allowed to dry, and the process is repeated until a half-inch thick or thicker dries coating covers the entire piece. The bigger the piece, the thicker the shell needs to be. Only the inside of the cup is not coated, and the cup's flat top serves as the base upon which the piece stands during this process.
8. Burnout. The ceramic shell-coated piece is placed cup-down in a kiln, whose heat hardens the silica coatings into a shell, and the wax melts and runs out. The melted wax can be recovered and reused, although often it is simply combusted by the burnout process. Now all that remains of the original artwork is the negative space, formerly occupied by the wax, inside the hardened ceramic shell. The feeder and vent tubes and cup are now hollow, also.
9. Testing. The ceramic shell is allowed to cool, then is tested to see if water will flow through the feeder and vent tubes as necessary. Cracks or leaks can be patched with thick refractory paste. To test the thickness, holes can be drilled into the shell, then patched.
10. Pouring. The shell is reheated in the kiln to harden the patches, then placed cup-upwards into a tub filled with sand. Bronze is melted in a crucible in a furnace, then poured carefully into the shell. If the shell were not hot, the temperature difference would shatter it. The bronze-filled shells are allowed to cool.
11. Release.The shell is hammered or sand-blasted away, releasing the rough bronze. The spruing, which are also faithfully recreated in metal, are cut off, to be reused in another casting.
12. Metal-chasing. Just as the wax copies were "chased," the bronze copies are worked until the telltale signs of casting are removed, and the sculptures again look like the original artwork. Pits left by air bubbles in the molten bronze are filled, and the stubs of spruing filed down and polished.
13. Patinating. The bronze is colored to the artist's preference, using chemicals applied to heated or cooled metal. Using heat is probably the most predicatable method, and allows the artist to have the most control over the process. This coloring is called patina, and is often green, black, white or brownish to simulate the surfaces of ancient bronze sculptures. (Ancient bronzes gained their patinas from oxidisation and other effects of being on Earth for many years.) However, with current artistic trends in the United States, many artists prefer that their bronzes have brighter, more stylized patinas. Patinas can be applied to replicate marble or stone. Depending on how the metal is prepared, either sandblasted or polished, the finish can be either opaque or transparent. After the patina is applied, a coating of wax, which is the most traditional type of sealer, is usually applied to protect the surface. Many artists prefer to use lacquer as a sealer on some of the more unstable patinas. This protects the piece more from ultraviolet rays. Some patinas change color over time because of oxidiation, and the wax layer slows this down somewhat.
On the left is an example of a lost-wax process mold, and on the right is the resulting bronze sculpture.
On the left is an example of a lost-wax process mold, and on the right is the resulting bronze sculpture.
The lost-wax process can also be used with any material that can burn, melt, or evaporate to leave a mold cavity. Some automobile manufacturers use a lost-foam technique to make engine blocks. The model in this case is made of polystyrene foam, which is then placed into a casting flask, consisting of a cope and drag, which is then filled with casting sand. The foam supports the sand, allowing shapes to be made which would not be possible if the process had to rely on the sand alone to hold its shape. The metal is then poured in, and the heat of the metal vaporizes the foam as the metal enters the mold.
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