The processing characteristics of stainless steel precision casting

author: kevin

2024-06-24

The processing characteristics of stainless steel precision casting

The mechanical properties of stainless steel precision casting are higher than cast iron, but its casting performance is worse than cast iron, and it belongs to investment casting or precision casting. Its melting point is high, the steel is prone to oxidation, the fluidity of the steel is poor, and the shrinkage is large. Stainless steel precision casting is not only suitable for casting various types and alloys.

The processing characteristics of stainless steel precision casting:

1. Due to the significant shrinkage of stainless steel precision casting compared to cast iron, in order to prevent shrinkage and porosity defects in castings, measures such as risers, cold iron, and subsidies are mostly used in the casting process to achieve sequential solidification.

To prevent shrinkage, porosity, porosity, and crack defects in stainless steel castings, the wall thickness should be uniform, sharp and right angle structures should be avoided, sawdust should be added to the mold sand, coke should be added to the core, and hollow cores and oil sand cores should be used to improve the yielding and breathability of the sand or core.

2. Due to the poor fluidity of molten steel, in order to prevent cold shuts and insufficient pouring in steel castings, the wall thickness of steel castings should not be less than 8mm; Using dry or hot casting molds; Appropriately increase the pouring temperature, generally between 1520 ° C and 1600 ° C, because the pouring temperature is high, the superheat of the molten steel is high, the liquid state is maintained for a long time, and the fluidity can be improved. However, if the pouring temperature is too high, it can cause defects such as coarse grains, hot cracking, porosity, and sand sticking. Therefore, for small, thin-walled, and complex shaped precision castings, the pouring temperature is approximately the melting point temperature of steel+150 ℃; The structure of the pouring system should strive for simplicity and the cross-sectional size should be larger than that of cast iron; The pouring temperature of large, thick walled castings is about 100 ℃ higher than their melting point.