Microstructure and Properties of 2Cr13-xMo Stainless Steels Fabricated by Direct Laser Deposition

In this paper, 2Cr13 stainless steels with different Mo contents (x = 0 wt%, 0.5 wt%, 1.0 wt%, 1.5 wt%, 2.0 wt%) were fabricated by Direct Laser Deposition (DLD) technology. The effects of Mo element on the microstructure evolution and comprehensive properties such as corrosion resistance and wear resistance of 2Cr13 stainless steel were investigated in detail. The results showed that the microstructure for the DLD 2Cr13 stainless steel was mainly composed of martensite, ferrite, and a small amount of -Mo2C and -Cr23C6 carbides. With the content of Mo increased from 0.5 to 1.5 wt%, the martensitic microstructure was refined and more dispersed -Mo2C and -Cr23C6 carbides were formed. The average microhardness and corrosion resistance of the DLD 2Cr(13-x)Mo were increased with the Mo content increased from 0 to 1.0 wt%, and then decreased when the Mo content exceeded 1.0 wt%. For the DLD 2Cr13-1.0 wt% Mo, the average microhardness reached up to 620 -HV0.2, and the highest corrosion resistance (self-corrosion potential - 0.34 V) was obtained, in which the selfcorrosion potential was 0.05 higher than that of DLD 2Cr13 stainless steel. The wear resistance of the DLD 2Cr13-xMo gradually increased with the increase of the Mo, the wear mass loss of DLD 2Cr(13-x)Mo (x = 1.0 wt%) was only 37% that of DLD 2Cr(13) stainless steel.