The Effect of Thermo-Mechanical Treatment on Mechanical Properties & Microstructure for (Cu-Al-Ni )Shape Memory Alloy

Abstract

This paper aims to study the effect of thermo mechanical treatment in different temperatures of (260 ,280& 300) ◦C on the microstructure and mechanical properties of Cu-14wt%Al-4.5wt%Ni shape memory alloy which prepared by casting method in induction furnace under argon atmosphere. Then thermo –mechanical treatment was performed upon the alloy by applying stress of 190MPa with heating upto 260◦C,280◦C,300◦C, then cooled to room temperature performingstrain recovery measurement. Many tests and inspections such as optical and SEM examinations , DSC Measurement ,XRD inspection , compression and Vickers hardness tests were investigated. The results showed that there is an increase in the transformation temperatures, shape memory limits at 300◦C .It was found that hardness increases and Young modulus decreases Also It was found that the thermo-mechanical treatment at 260 ◦C gave better properties , 2%in recovery strain , increase hardness due to the formation of martensitic phase and austenite phase in structure.

Keywords

• base shape memory alloys
• mechanical properties
• shape memory effect