Abrasive waterjet peening with elastic prestress: A parametric evaluation

Abstract

Abrasive waterjet peening (AWJP) has emerged as a potentially viable method of surface treatment for metal orthopedic devices. In this study the influences of AWJP with elastic prestress on the surface and subsurface residual stress distributions and surface texture of spring steel (ASTM 228) as well as titanium (Ti6Al4V) and nickel (inconel 718) alloys were studied. A design of experiments (DOE) and an analysis of variance (ANOVA) were used to identify the parameters with primary contributions to the dependent variables. Surface residual stress resulting from AWJP ranged from 500 to 2500 MPa, and the depth of compressive residual stress ranged from nearly 80 to 600 μm. While the elastic prestress had no effect on the surface texture, it was a primary contributor to the magnitude of surface residual stress, which increased with an increase in the elastic prestress. According to the results of this study, AWJP with elastic prestress can serve as a viable method of surface treatment in situations that require an increase in surface roughness and a compressive residual stress.