The Use of Thermal Analysis for Generation of Fraction Solid Evolution in Al-Si Alloys

Abstract Solidification shrinkage induced defects, generally referred to as shrinkage cavities and shrinkage porosities, have negative consequences ranging from high rework costs to casting rejection that produce significant negative economic impact. Recently developed simulation tools used to predict porosity distribution in casting alloys depend on the calculation of fraction solid during solidification, which is highly dependent on the local solidification rate. Predicting such rates with standard solidification software is inadequate, as most software are unable to include in the calculation the real solidification kinetics that is highly dependent on the nucleation and growth of phases. The solution is to use fraction solid based on the experimental local solidification conditions. The goal of this work is to develop a thermal analysis method/equipment that can record and generate in-time evolution of fraction solid for local casting conditions in any casting shape or size. To this goal, results obtained on designed experiments are analyzed through Newtonian and Fourier calculations and compared with literature data.