Effect of Shot Peening on Ballistic Limit of Al6061-T651 Aluminium Alloy Plates

A series of impact experiments were conducted to Al6061-T651 plates to investigate the effect of shot peening to the ballistic limit. The experiments were carried out by a gas gun set-up and tungsten-based cube projectiles were employed. During the experiments, projectiles were impacted on the target plates either from the shot peened-surface or from the back-surface. The ballistic limits were obtained for the base plate and two shot peened-target plates processed with two different Almen intensities, 12A and 16A. In addition, hardness, residual stress and surface roughness measurements as well as elemental analysis were conducted for the base plate and shot peened plates. According to the experimental work, it was concluded that despite the hardness increase and compressive residual stress fields, two well-known benefits of shot peening for fatigue life enhancement, shot peening did not offer a significant improvement in the ballistic limit for the projectile-target set-up used in this study.