Effect of shot blasting on plain fatigue and fretting fatigue behaviour of Al-Mg-Si alloy AA6061

The present work describes the effect of shot blasting on plain fatigue (without fretting) and fretting fatigue behaviour of Al-Mg-Si alloy AA6061. Shot blasting significantly increased the plain fatigue life by a factor 2.8 and fretting fatigue life by a factor 2.4 at a maximum cyclic stress (σmax) of 169 MPa, but at higher stress levels shot blasting slightly reduced both the plain fatigue and the fretting fatigue lives. At a maximum cyclic stress of 169 MPa, the stabilized value of coefficient of friction in the shot blasted condition was lower than that in the T6 condition (0.55 against 0.60), but at a maximum cyclic stress of 265 MPa, it was around 0.82 in the T6 condition and 0.84 in the shot blasted condition.