Effect of Squeeze Casting on Microstructure and Wear Properties of Aluminium Al–Si Alloy

Abstract

Lightweight materials are of increasing interest to automotive and aerospace industries owing to their high specific strength and potential for reducing environmental impact due to lower CO2 emissions. It has been found that many cast iron components are replaced by pure aluminium or aluminium alloy components which are manufactured by pressure-assisted casting operations. The application of pressure during solidification in squeeze casting improves mechanical properties, creates smoother surfaces and reduces porosities. In this work, the results highlight the effect of pressure-assisted casting (squeeze casting) process on microstructure, hardness and wear-resisting properties like fretting wear and dry sliding wear of Al–Si A356 alloy. It was observed that there was significant change in the microstructural characteristics like reduction in secondary dendrite arm spacings of α-Al phase/matrix, change in the eutectic Si morphology, reduction in microporosities. Effective precipitation of intermetallics was found to occur after heat treatment whereas mechanical properties like hardness and wear-resistant properties during fretting wear and dry sliding wear got improved on squeeze casting. © 2020, Springer Nature Singapore Pte Ltd.