The Effect of Cryogenic Treatment on the Microstructure and Mechanical Properties of 301 Stainless Steel

This paper adopted a novel cryogenic treatment to 301 stainless steel, and investigated the effect of cryogenic treatment on microstructure and mechanical properties of the experimental steel by OM/TEM/XRD/tensile test. Compared with the samples without cryogenic treatment, the cryogenic treatment made the austenite width refined from 0.20 to 0.15 mu m and made the martensite lath width from 0.18 to 0.13 mu m. The austenite content decreased by about 12 vol.% after cryogenic treatment. It should be noted that the dislocation density and precipitates density in experimental samples also increased after cryogenic treatment. The cryogenic treatment made the yield strength increase about 200 MPa by various hardening mechanisms and made the ultimate tensile strength increase from 1610 to 1830 MPa, and also increased the total elongation from 16 to 25%.