Evaluating the Mechanical Properties of HPT Processed Aluminium Alloys Using Automated Ball-indentation Technique

Al-Cu and Al-Zn-Mg alloys exhibit excellent physical and mechanical properties, and are widely used for aerospace applications. However, these properties may be further improved through high-pressure torsion (HPT) processing. HPT processing was carried out on Al-2014 alloy and Al-7475 alloy to investigate the improvement in mechanical properties. Disks of coarse-grained Al- 2014 alloy and Al-7475 alloy were processed up to two turns of HPT, and the mechanical properties were evaluated using automated ball indentation (ABI) technique. HPT processing was carried out at atmospheric temperature, under pressure of 6 GPa. The results show that, for Al-2014 alloy the ultimate tensile strength at the edge of HPT disk increased by a factor of ∼ 4, after 2 turns of HPT processing. Since, ABI technique provides the capability of obtaining extensive mechanical data using only a very small sample; it is an ideal procedure for evaluating the mechanical properties of samples processed by HPT.