Phase transformations in stainless Cr–Mn–N steel activated by nanostructuring surface treatment and their influence on deformation behavior and fracture at cryogenic temperatures

The structure of stainless austenitic Cr–Mn–N steel after deformation treatment of its surface by ultrasonic forging strain (UFS) has been studied. It is shown that UFS activates strain aging in the near-surface layer with the formation of CrN particles. Preliminary ultrasonic treatment of the steel surface contributes to an increase in the yield strength during tensile tests at a temperature of -196$^\circ$C and provides ductile fracture of the near-surface layer.