Heat Treatment Map of Al2Ca-added AlSi11MnMg Pressure-Cast Alloy Plotted by Full Factorial Design of Experiment and Analysis of Variance

Abstract

The methods of design of experiment (DOE), analysis of variance (ANOVA) and response surface (RS) are used to study the effect of heat treatment on the microstructure and mechanical properties of a novel AlSi11MgMn pressure-cast alloy with an addition of Al₂Ca. After the high-pressure casting, the specimens are solution treated at 490°C for 15 min and quenched in cold water. After the solution treatment, the morphology of the eutectic silicon changes, the elongation increases, and the yield strength and the ultimate strength decrease. The effect of the aging temperature and time on the tensile mechanical properties is studied by 4 × 4 full factorial design of experiment. The response surface is plotted for the ultimate and yield strengths and for the elongation; three equations predicting satisfactorily the mechanical properties of the alloy as a function of the aging temperature and time are derived.