How to shell stainless steel Investment casting?

The production process of stainless steel Investment Castings is relatively complex, and the requirements for dimensional accuracy are high. The shell making processes of stainless steel precision castings are mainly divided into three types, namely water glass process, silica sol process and silica sol composite process. Now, let's introduce them one by one.

Stainless Steel Casting

1. Compared with the silica sol shell, the sodium silicate shell retains the sodium silicate binder, so the overall high temperature resistance, deformation resistance and casting size accuracy of the shell are lower than those of the silica sol shell. The casting surface produced by sodium silicate process is relatively rough, and sand hole and shrinkage porosity are common. However, its production cost is low, so most casting manufacturers will choose this process for casting production.

2. The castings produced by the silica sol process have high dimensional accuracy, high surface finish and precision, which are suitable for the production of high-quality precision castings, but the cost is high.

3. The silica sol composite process is between the water glass process and the silica sol process. Its quality stability is better than that of sodium silicate but inferior to that of silica sol process. The surface finish and product quality of the castings produced are better than that of sodium silicate, but the production cost is much lower than that of silica sol process. Therefore, foundry manufacturers are more inclined to choose silica sol composite process when producing a large number of mechanical products.