Effection Of Low Temperature GAS Multicomponent Penetrating On Properties And Cavitation Resistance Of ZG04Cr13Ni5Mo

Chinese companies have reached the advanced level in design and manufacturing capability of hydropower equipment, but the problems of cavitation, wear and cracks of turbine runner has not been solved effectively.In the sutdy, we applied low temperature gas multicomponent penetrating to the ZG04Cr13Ni5Mo martensitic stainless steel and researched mechanical properties, fatigue performance, wear resistance, corrosion resistance and cavitation resistance of the treated material. The results show that:A hardened layer about 70μm thick formed on the surface of ZG04Cr13Ni5Mo which composed of oxide layer, dispersive ε-Fe2-3 (N, C) compound layer and diffusion layer.There is no change for the center structure,low carbon lath martensite and a small amount of delta ferrite. The surface hardness(1250HV)is five times the hardness of the center.By low temperature gas multicomponent penetrating, the strength and ductility of ZG04Crl3Ni5Mo don’t change,but the impact energy will decrease slightly because energy of crack forming and extension is lower than that of untreated specimen. By low temperature gas multicomponent penetrating, the surface of ZG04Cr13Ni5Mo with residual compressive stress and higher hardness enhance the fatigue and wear resistance significantly.By low temperature gas multicomponent penetrating, chromium combined with the permeated C and N and the effective composition of chromium reduced. So the corrosion resistance of ZG04Crl3Ni5Mo decreasedThe principle of cavitation is too complicated to corresponding to some specific physical and chemical nature of the material. And according to mechanism of mechanical action of cavitation, hardness and fatigue are helpful to the cavitation for the same material and that has been proved by the study:by low temperature gas multicomponent penetrating, the cavitation resistance of ZG04Cr13Ni5Mo increased significantly.