Residual stresses assessment on waterjet peening metallic biomaterials by thermoelectric magnetic sensing

Abstract

The superficial treatment for metallic materials with water jet peening is oriented to improve the mechanical fixation of implants through an increase in roughness. Because of superficial plastic deformation, additional subsurface material effects occur such as grain refinement, hardening, increased compressive residual stresses and cold worked; which are generally evaluated by destructive tests. This research is focused on the analysis of these subsurface material effects by a non-destructive technique such as the non-contact thermoelectric power (TEP) inspection using a magnetic sensor to detect thermoelectric currents induced by a temperature gradient in water jet peened 316LVM austenitic stainless-steel and Ti-6Al-4 V ELI titanium alloy samples. The results obtained by magnetic TEP non-destructive test versus the X-ray diffraction technique are compared. It was found that it is possible to qualitatively characterize some of the subsurface material effects mainly residual stresses and cold working produced by deformation through surface treatment with blasting of water.