Effect of Shear Direction on Work-Hardening Evolution of AISI 409 Steel Under Rolling/Shearing Loading

Abstract The mechanical behavior of metallic materials depends on several variables, such as the material structural characteristics, the process parameters, the temperature, the strain rate and the anisotropy features due to strain paths in different metal forming operations. Considering the last one, the effect of shear direction loading on the work-hardening after the rolling/shearing loading of a ferritic stainless steel, AISI 409, was investigated in this work. The annealed AISI 409 sheets were predeformed by cold rolling up 0.19 effective strain and then sheared at three different directions: at 0°, 45° and 90° from the original rolling direction. The samples were characterized through tensile, shear and Vickers microhardness tests while the study of crystallographic texture was performed using the electron backscatter diffraction (EBSD) technique. The work-hardening behaviour of the material was analyzed considering the work-hardening rate and the Hollomon work-hardening exponent after each strain path change applied to the AISI 409 steel. The results indicated the presence of preferential crystallographic orientation and the occurrence of transients on the work-hardening rate mainly for the sample sheared at 45° from the original rolling direction due to structural arrangements assumed by the AISI 409 steel after the strain path changes.