Simulation of the solidification organization of X15CrNiSi20-12 alloy castings during investment casting based on the CAFE model

Abstract

In this work, the CAFE (Cellular Automata Finite Element) model was used to simulate the grain growth of X15CrNiSi20-12 austenitic stainless steel during the investment casting process, and the effects of shell thickness, shell temperature, casting temperature, and cooling rate on the solidification organization were investigated by orthogonal tests. The results show that the cooling method has an important effect on the formation of equiaxed crystals. However, the shell temperature, shell thickness, and casting temperature have a smaller effect on the formation of equiaxed crystals. A more equiaxed fine grain structure can be obtained by using a shell thickness of 7 mm, shell temperature of 1143.15 K, casting temperature of 1913.15 K, and water-cooling conditions. In addition, a decrease in the shell thickness, shell temperature, and casting temperature can lead to an increase in the grain size, while an increase in the cooling rate will lead to smaller grain size and increase the number of equiaxed fine crystals, thus improving the mechanical properties of the material.