Performance Analysis of Laser Cladding M2 Coating on 20Cr13 Stainless Steel
M2 coating was prepared on the surface of 20Cr13 substrate by laser cladding technology.The macro-morphology,microstructure,phase composition and microhardness of the M2 coating were analyzed by ultra-depth microscope,optical microscope,XRD and Vickers hardness tester.The Tafel curves and corrosion forms of the M2 coating and 20Crl3 substrate were measured by electrochemical workstation.The results show that the main phases of the coating areα-Fe and carbide hard phases(M23C6 and M7C3),forming good metallurgical bonding with the substrate.The average hardness of the coating is 729.5 HV,which is 3.8 times of the average hardness of the substrate.The self-corrosion potential of the substrate is largest and the self-corrosion current density is smallest,and the corrosion resistance of the coating is worse than that of substrate.The corrosion form of the cladding layer is mainly pitting and intergranular corrosion,and the substrate is mainly hole and intergranular corrosion.