Influence of Processing Conditions on Properties of AISI 316LN Steel Grade

The influence of rolling temperatures performed at ambient and cryogenic conditions in the interval of deformations e =   (%) on structural development and mechanical properties of steel grade AISI 316LN was studied. The evaluations of microstructures were studied by optical and transmission electron microscopy. The initial strength properties of the material after solution annealing tested at 293 K were: RP0,2 = 325 MPa, Rm = 640 MPa, and A5 = 49%. The biggest values of strength properties were obtained by material processing at cryorolling conditions with thickness reduction of 50% and tested at 77 K as follows: RP0,2 = 1571 MPa, Rm = 1880 MPa, and A5 = 4%. From the analysis, it is resulted that the dislocation slip is the main mechanism of plastic deformation realized by rolling at ambient temperatures; at cryogenic temperatures, it is possible to observe a combination of dislocation slip accompanied with deformation twinning.