Effect Of Shot Peening Methods On The Fatigue Behaviour Of Alloy 7075-t6

Author:  Was, Pelloux, Frabolot
Source:  Conf Proc: ICSP-1, (p.445-452)
Doc ID:  1981018
Year of Publication:  1981
Abstract:  
The effect of wet and dry shot-peening methods on the reverse bending and uniaxial fatigue behavior of A1 alloy 7075-T5 is investigated. Fatigue specimens were shot peened in both the conventional manner (dry surface) and while coated with a thin film of mineral oil (improved process) to reduce surface roughening and increase the residual stress in the workpiece in excess of that due to dry impact. In reverse bending tests, conventional dry surface peening increases fatigue strength relative to unpeened specimens. Peening with an oil film failed to produce a significant systematic improvement in fatigue behavior over the dry peening process. In uniaxial tension--compression fatigue with zero mean stress, the two peening methods produce nearly identical results; and increase in lifetime at high stresses and very little change near the fatigue limit. Descirptors: Aluminum base alloys-- Mechanical properties; Shot peening; Fatigue limit; Residual stress