Experimental research on surface reinforcement mechanism introduced by coupling effect of cutting forces and heat

HSC (High Speed Cutting) of ultra-high strength steel was conducted in a design of statistic analysis to investigate the coupling effect of mechanical load and thermal load on the surface quality of workpieces. The experimentation demonstrated that the HSC machined surfaces could exhibit significant changes in the surface quality, such as low surface roughness (Ra < 0.4 μm), free of micro-cracks, and reasonable residual stress profiles. The micro-hardness on the surface and sub-surface layer was remarkably increased, the maximum compressive residual stress value was dramatic increased and the compressive residual stress could notably expand to 0.35 mm beneath the machined surfaces. This study indicated that the properly controlled HSC process could be used as a high efficient surface strengthening method which could significantly increase the workpiece's microstructure properties and service performances with high material remove rate.