Pure metals are rarely used in casting production, and various alloys are generally used. In addition to the mechanical properties, physical and chemical properties that meet the requirements, the casting energy of casting alloy must also be considered. The casting properties of the alloy mainly include fluidity and shrinkage segregation, which are very important for obtaining sound castings easily.
In, the ability of liquid metal to fill the mold is the basic condition to obtain complete shape, accurate size and clear profile casting. However, the liquid metal in the filling process is accompanied by crystallization due to heat dissipation. At the same time, there is resistance of the mold to the liquid metal, as well as the back pressure of the gas in the mold cavity, which hinder the smooth filling of the liquid metal. If the fluidity of the metal is not enough, the metal will stop flowing before it has filled the mold, and the casting will have insufficient pouring or cold insulation defects.
The fluidity of alloy refers to the fluidity of liquid metal itself and the ability of filling mold. The better the fluidity of alloy, the stronger the ability of liquid metal filling mold. Therefore, the fluidity of alloy is often summarized as the ability of liquid metal filling mold. Alloy fluidity is one of the important casting properties of alloy. The better the fluidity is, the easier it is to cast thin and complex castings with clear profile. At the same time, it is also conducive to the floatation and removal of non-metallic inclusions and gases in the liquid metal, and is easy to supplement the shrinkage produced in the solidification process of the liquid metal. Therefore, the fluidity of alloy must be considered in the design of casting and the formulation of.