Solid fraction analysis during liquid metal solidification of casting bed parts

Because hot joints will occur in large and thick parts during the cooling process of castings, and casting defects such as shrinkage and voids are easy to occur, the change process of solid fraction during solidification of castings is analyzed to analyze the possible positions of hot joints, and all hot joints are eliminated by optimization. Generally, cold iron is put near the hot joints and heat transfer is accelerated to eliminate hot joints.

The figure shows the solidification rate change process of the bed castings.By analyzing the solid phase ratio of the casting, it is found that the whole is close to and solidified at the same time. Only the right angle contact area at the bottom of the casting is slightly slower than the whole. If these areas can not be compensated in time, shrinkage holes will be formed at the final solidification of the casting.However, as the wall thickness of the casting is basically uniform and the large part is relatively thin, the graphitized expansion of the casting is larger than the shrinkage, so there are no defects in the large part.