Improvement of structural design accuracy using a casting-structural interface(CSI) method in large-scale sand castings

다국어 초록 (Multilingual Abstract)

In general, thermal residual stress is generated in casting products as a result of non-uniform cooling, phase transformation from liquidto solid states, and thermo-mechanical constraints. Thus, understanding accurate stress distributions is important in designing a castingpart to predict its real structural stability. However, the residual stress that occurs in the casting process is often not considered in themechanical design process to reduce engineering efforts and time. We conducted a structural analysis that compares two cases with andwithout considering casting residual stress in large-scale sand castings and obtained significantly different results. We introduced an interfacingalgorithm (casting-structural interface) to map the casting residual stress with structural stress and combined the results of finitedifferent analysis for casting and finite element analysis for structural design. This work represents our preliminary studies on improvingthe design accuracy of a large-scale casting part and shows the importance of considering the casting residual stress. A difference ofabout 41% in maximal principle stress is obtained with and without considering the casting residual stress.

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