In order to eliminate the adverse effect of hot spot, reduce the defects of ductile iron spent fuel container and ensure that the structure and properties meet the requirements, Germany adopts sand mold cold iron casting process in hot spot.
Through simulation and experimental research, metal mold is used on the outer side of the body, direct external chill is used on the inner side of the body, and metal mold + whole chill (hereinafter referred to as full chill) is used on the top hot spot. The simulation software is used to compare the solidification characteristics of sand mold chill process and the process in this project. The geometric models of different casting processes are shown in the figure. Compared with the simulation results, the process of spent fuel container was optimized.