Investigation on tribological behaviors of surface micro-forming 20CrNiMo steel under laser shock processing

In order to study tribological behaviors of surface micro-forming 20CrNiMo steel under laser shock processing(LSP),the effects of LSP on the friction and wear behaviors of 20CrNiMo steel were investigated through observing micro-structure and measuring the macro-surface profile.Firstly,20CrNiMo was impacted by overlapping LSP in different overlap ratio,and then micro-structure of surface layer was observed through transmission electron microscope,finally,the pictures for surface layer grain state were obtained.Friction and wear test was conducted by CETR UMT Tribometer,surface friction coefficient and wear volume was obtained.The results indicate that grain refinement happens in the surface layer due to LSP impacting 20CrNiMo.Friction and wear behaviors can be improved obviously because fine grain in the grain refinement layer can restrain fatigue wear on lubricated sliding wear process effectively.