Copper Casting

1.Material:Ductile  iron,Iron,stainless Steel,Carbon Steel, Alloy Steel,  Aluminum,  brass, or  on  request  of  customer2.Process:Silicasol  casting process  and  machining.3.Weight  range:0.01-150KG4.Size:As per the customer's drawings and requirements5.SurfaceTreatment:painting,polishing,  galvanization etc  and  as  per  customers"  requirement6.Heat  Treatment:Annealing,  normalizing  ,quenching+tempering,solution  treatment  and  as  per  customer's  requirement.7.Inspection:Factory  in-house  self  check  or  Third  Party  inspection8.Certificate:ISO9001-20089.Delivery:By  sea,  air  or  express  according  to  customers'  requirementFAQ:1. Are you a factory or trade company?-------We are a factory. We provide you one-stop service, from mold design to finish part.2. Where is your factory?-------Our factory located on WuXi which is a beautiful city near from ShangHai and famous for Custom product.3.How to order?-------First, Customers could send us your sample drawing, such as 2D and 3D drawing(IGS or STP format)Second, Our engineers will check the drawing carefully and then provide you a better price.Third, If you accept, then order confirmed.4.Your price is very high and i can get more lower price from other supplier.-------First, You can always get some lower price from some suppliers in China. There is no lowest price in China at all. there is only much lower price one by one.Of course, if you could bear various kinds of bad problems and invalid commitment of cheaper productions. Their price is cheaper $ 1 than us and you can earn 10000 USD on 10000 pcs parts. But you will lose more than 10000 USD, even more lose a faithful customer if it happend a mechanical mishap occur. At the same time, I don't think you can get more higher efficiency of the supply when you get a price which is lower 0.5-1 USD because price elasticity depends on different service.Finally, you are an expert in the filed, if they can give you an offer which is even lower than the cost. What will you think about it.What you will get is what you paid for.5. What are your main products?Precision casting parts, sand casting parts, machining parts, surface treatment parts, etc.Copper and Copper Alloys Casting ProblemsPure copper is extremely difficult to cast as well as being prone to surface cracking, porosity problems, and to the formation of internal cavities. The casting characteristics of copper can be improved by the addition of small amounts of elements including beryllium, silicon, nickel, tin, zinc, chromium and silver.Copper alloys in cast form (designated in UNS numbering system as C80000 to C99999) are specified when factors such as tensile and compressive strength, wear qualities when subjected to metal-to-metal contact, machinability, thermal and electrical conductivity, appearance, and corrosion resistance are considerations for maximizing product performance. Cast copper alloys are used for applications such as bearings, bushings, gears, fittings, valve bodies, and miscellaneous components for the chemical processing industry. These alloys are poured into many types of castings such as sand, shell, investment, permanent mold, chemical sand, centrifugal, and die casting.The copper-base casting alloy family can be subdivided into three groups according to solidification (freezing range). Unlike pure metals, alloys solidify over a range of temperatures. Solidification begins when the temperature drops below the liquidus; it is completed when the temperature reaches the solidus. The liquidus is the temperature at which the metal begins to freeze, and the solidus is the temperature at which the metal is completely frozen.Group I alloysGroup II alloys……Group III alloysGroup III alloys have a wide freezing range. These alloys have a freezing range of well over 110oC, even up to 170oC. Group III alloys are: leaded red brass (C83450, C83600, C83800), leaded semi-red brasses (C8400, C84800), tin bronze (C90300, C90500, C90700, C91100, C91300), leaded tin bronze (C92200, C92300, C92600, C92700), high-leaded tin bronze (C92900, C93200, C93400, C93500, C93700, C93800, C94300).These alloys, namely leaded red and semi-red brasses, tin and leaded tin bronzes, and high-leaded tin bronzes, are treated the same in regard to melting and fluxing and thus can be discussed together. Because of the long freezing ranges involved, it has been found that chilling, or the creation of a steep thermal gradient, is far better than using only feeders or risers. Chills and risers should be used in conjunction with each other for these alloys. For this reason, the best pouring temperature is the lowest one that will pour the molds without having misruns or cold shuts. In a well-operated foundry, each pattern should have a pouring temperature, which is maintained by use of an immersion pyrometer.Fluxing. In regard to fluxing, these alloys should be melted from charges comprised of ingot and clean, sand free gates and risers. The melting should be done quickly in a slightly oxidizing atmosphere. When handled at the proper furnace temperature and cooled to the proper pouring temperature, the crucible is removed or the metal is tapped into a ladle. At this point, a deoxidizer (15% phosphor copper) is added. The phosphorus is a reducing agent (deoxidizer). This product must be carefully measured so that enough oxygen is removed, yet a small amount remains to improve fluidity. This residual level of phosphorus must be closely controlled by chemical analysis to a range between 0.010 and 0.020% P. If more is present, internal porosity may occur and cause leakage if castings are machined and pressure tested.In addition to phosphor copper, pure zinc should be added at the point at which skimming and temperature testing take place prior to pouring. This replaces the zinc lost by vaporization during melting and superheating. With these alloys, cover fluxes are seldom used. In some foundries in which combustion cannot be properly controlled, oxidizing fluxes are added during melting, followed by final deoxidation by phosphor copper.