A Comparison between Numerical Simulation and Experimental Determination of Porosity

Porosity is one of the major defects in aluminum castings, which is induced by several mechanisms (solidification shrinkage and gas segregation). One of the methods for complex evaluation of macro and micro porosity in Al-Si alloys is Tatur test technique. This article deals with evaluation of porosity with help of Tatur test for an Al-Si alloy. The simulation tests were conducted using commercial FEM based software. The simulation results obtained using ProCAST software will be compared with experimental measurement of porosity. Comparison has shown good agreement of simulation and experiment in predicting and localizing the major defects of shrinkage except for slump defect in top part of the casting which would mean, that the solidification modeling included in the tested software does not reflect phenomena responsible for the solidification processes in real castings properly. Further tests, with different types of software and more fundamental studies on the solidification process modeling would be desirable.