Numerical simulation of the cooling phase of a sand casting for the evaluation of residual stresses


Politecnico di Bari


The prediction of residual stress after a casting process is becoming a source of concern in most of the engineering applications, since a residual state of stress is able to negatively influence both the performance of the component and its manufacturing. A big help toward such a prediction comes from the numerical simulation, which is of course based on robust numerical models (in which both mechanical and thermo-physical properties of the investigated alloy are properly implemented).
Since a reliable temperature evolution of different casting zones is the key factor in order to effectively and efficiently model the thermal stresses in a casting, an optimized inverse analysis procedure has been used in this work implementing a Finite Element based node within the modeFrontier workflow. Such an approach allowed to determine the interface Heating Transfer Coefficients able to fit the numerical temperature evolutions acquired from instrumented casting experiments.
The Finite Element model able to reproduce the thermal field of the casting during the cooling was finally used for estimating thermal and residual stresses on the part.