Effect of Cold Rolling on Microstructure and Mechanical Properties of AISI 304N Stainless Steel

Abstract

Effect of cold rolling at room temperature on microstructure and mechanical properties of a nitrogen-bearing austenitic stainless steel AISI 304N was studied in this paper. The cold rolling reductions from 5% to 90% were adopted for the cold rolling test. Microstructures were observed by an optical microscopy, volume fractions of strain induced α’-martensite were measured by a ferritescope, and deformation induced transformation was investigated by X-ray diffraction. Hardness and tensile tests were carried out to determine the mechanical properties. The results showed that with increase of cold rolling reduction, the volume fraction of strain induced α’-martensite increased while grains were elongated along the rolling direction. The formation of α’-martensite and the lamellar grains resulted in the significant strengthening of the steel and substantial decrease of elongation.