Tribological properties of laser textured surfaces of 45# steel under dry friction

The surface textures on 45# steel were produced with a Q switched solid-state Nd:YAG laser. Friction tests were performed using a pin-on-disk apparatus. The effect of micro-texturing under dry friction was analyzed. The morphologies of the texture and wear scar of the samples were observed using a 3D profiler and scanning electron microscopy. The result showed that the regular micro-dimple texture was produced on the surface of 45# steel by laser. Laser-textured specimens exhibited lower and stable friction coefficient as compared with untextured specimens under dry friction. The textured surfaces also exhibited lower wear rate than that of untextured specimens. It was found that micro-dimples acted as traps for wear debris, and hence decreased abrasive wear. The effects of dimple area density and dimple diameter on the tribological properties were also investigated. It was found that larger dimple area density and larger dimple diameter were in favor of friction-reduction and wear resistance.