The novel low cost as-casting Al-based composites with high strength and ductility

Abstract

In this paper, three alloys Al _81 Cu _13 Si _6 , Al _88 Cu _8 Si _4 and Al _92 Cu _5.6 Si _2.4 were prepared by a simple solidification process. By controlling the alloy composition, different microstructures and mechanical properties have been achieved. The Al _81 Cu _13 Si _6 alloy with micro-scale binary eutectic compositions embedded in an ultrafine ternary eutectic matrix exhibits the high yield strength (up to 750 MPa) but fails with a brittle fracture. While the Al _92 Cu _5.6 Si _2.4 alloy with hypereutectic composite structure exhibits the optimum comprehensive mechanical properties with both high tensile strength and ductility. The present results provide a new perspective to prepare Al-based alloy with high strength and ductility by designing the some new composite with optimum microstructure.

Keywords

• Al–Cu–Si alloy
• ductility
• lightweight alloys