Development the Mechanical Properties of (AL-Li-Cu) Alloy

Abstract

The aim of this research is to develop mechanical properties of a new aluminium-lithium-copper alloy. This alloy prepared under control atmosphere by casting in a permanent metal mould. The microstructure was examined and mechanical properties were tested before and after heat treatment to study the influence of heat treatment on its mechanical properties including; modulus of elasticity, tensile strength, impact, and fatigue. The results showed that the modulus of elasticity of the prepared alloy is higher than standard alloy about 2%. While the alloy that heat treated for 6 h and cooled in water, then showed a higher ultimate tensile stress comparing with as-cast alloy. The homogenous heat treatment gives best fatigue behaviour comparing with as-cast and other heat treatment alloys. Also, the impact test illustrates that the homogeneous heat treatment alloy gives the highest value.

Keywords

• aluminium-lithium alloys, heat treatment, microstructure, mechanical properties