Simulation of Dimensional Changes and Hot Tears During Solidification of Steel Castings
Cracks, or “hot tears,” may form in a steel casting during the late stage of solidification and would occur when contractions can no longer be accommodated by residual liquid flow or solid displacement. During the subsequent cooling of the solidified steel, contractions and distortions of the steel known as “dimensional changes” can cause the final product to vary significantly from the original pattern. The occurrence of hot teats and dimensional changes are hard to anticipate and correct using traditional foundry engineering methods. Research conducted by the University of Iowa has shown that hot tears are initiated in the residual liquid which is ruptured by contraction strain. Some successes have been reported in predicting the final dimensions of and residual stresses in castings using stress analysis. This project will combine the stress analysis and feeding flow/porosity models to form a model that predicts dimensional changes and hot tears during the solidification process of steel castings.