Investigation on wear resistance of nodular cast iron by laser surface treatment

The surface of nodular cast iron was treated by laser melting and quenching with 5 kW CO2 laser. The corresponding effect on hardness, microstructure was studied. And a comparison between the tribological behaviour of the laser quenched and laser melted ductile cast iron was presented. The results show that the material hardness after laser surface treatment processes (LST) was significantly improved, and the hardness of the area treated by the laser melting is slightly higher than that of the laser quenching treatment. And LST enhanced the microstructure and the wear resistance of the nodular cast iron. The analysis shows that the wear resistance of the area after heat treatment was obviously improved compared with that of the substrate but the laser quenching has more obvious influence on the wear resistance than the laser melting.