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, 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. Metal Casting and save molding materials, can reduce environmental pollution, improve working conditions.
It is not suitable to produce large and complex thin-walled castings with high manufacturing cost. Because of the fast cooling speed, the surface of cast iron is easy to produce white mouth, Metal Casting 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. 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.
In order to enable castings to be removed in a timely manner from the casting type, most metal types have a casting mechanism. When casting with metal, the inner cavity of the casting can be obtained with a metal core or a sand core, Metal Casting and the metal core is usually used only for non-ferrous castings. In order to remove the metal core from the complex inner cavity, Metal Casting a combined metal core can be applied.