Metal casting, commonly known as hard die casting, is made of cast iron, steel or other metal materials, and in the gravity of the metal liquid into the mold to obtain the casting process. Because a pair of metal life long, can be poured thousands of or even tens of thousands of times, so metal casting is also known as permanent casting.
The characteristics of metal casting are as follows.
(1) There is a higher dimension precision (it12~it16) and a smaller surface roughness (Ra6.3μm~12.5μm), the machining allowance is small.
(2) Because of the good heat conductivity of metal type, Metal Casting the cooling speed is fast, the grains of the castings are finer and the mechanical properties are good.
(3) can realize "one type multiple casts", raise labor productivity. and save molding materials, can reduce environmental pollution, improve working conditions.
However, the trade network points out that the manufacturing cost of metal mold is high, and it is not suitable to produce large and complex thin-walled castings. Metal Casting Because of the fast cooling speed, the surface of cast iron is easy to produce white mouth, which makes the machining difficult. The alloy with high melting point is not suitable for metal casting because of the limit of the melting point of the metal type material.
Metal casting is mainly used for mass production of non-ferrous castings such as copper alloy and aluminum alloy, such as piston, connecting rod, cylinder head, bushing, bushing, etc. Metal Casting Cast iron parts of the metal casting has also developed, but its size limit within the MM, the quality of not more than 8kg, such as the bottom of an electric iron.
Metal casting generally can be ct6~ CT9 scale accuracy, surface roughness RA up to 3.2μm. 3 The quality of castings is stable, the scrap rate is lower, the process yield is high, the material is saved and the cost is reduced.
1 because the metal mold thermal conductivity and thermal capacity of large, cooling speed, Metal Casting metal crystal microstructure is relatively close, less segregation, so the mechanical properties of castings are generally more than 15 of the sand-type castings.
2 castings with higher dimensional accuracy and lower surface roughness, metal casting generally can be ct6~ CT9 class size accuracy, surface roughness RA up to 3.2μm.
3 The quality of castings is stable, the scrap rate is lower, Metal Casting the process yield is high, the material is saved and the cost is reduced.
Metal casting can reduce the dosage of $number sand, or even completely use sand, save the sand transportation and sand processing equipment, costs and a lot of manpower, reduce the dust and harmful gas hazards, improve the working environment.
4 labor productivity is higher, Metal Casting easy to realize mechanization and automation, technology easy to master.
5 The Workshop unit area production is higher.