Influence of shot peening and laser ablation on residual stress state and phase composition of cemented carbide cutting inserts

Abstract

Substrate residual stresses in coated carbide tools are a result of pre-coating and coating processes. One prominent PVD pre-coating process is shot peening, that in addition to the necessary surface pre-treatment, induces compressive residual stress into the substrate's subsurface. Shot peening processes performed with different parameters and their influence on residual stresses are investigated and evaluated. A novel method for shaping carbide cutting tools is given by laser ablation. This process gives rise to heating of the specimen's subsurface. Hence, it can be expected, that tensile residual stresses are created. Laser ablation processes with different parameters have been performed and their influence on residual stress depth distribution has been determined.