Thermal fatigue resistance of H13 steel treated by selective laser surface melting and CrNi alloying

► Selective CO2 laser surface melting and alloying technologies were adopted. ► Thermal fatigue resistance of H13 steel is improved. ► Thermal fatigue resistance would be enhanced remarkably by laser alloying with 75%Cr25%Ni mixed powder. ► Laser alloyed zone has excellent properties such as resisting crack initiation and oxidation corrosion. ► Cracks and oxidation corrosions are restricted within narrow limits structured by laser scanning tracks.