Effect of cold single-roll drive rolling on the microstructural evolution and mechanical properties of ferritic stainless steel
Hossein Aghamohammadi, Roohollah Jamaati
Abstract
In this study, the microstructural evolution and mechanical behavior of AISI 430 ferritic stainless steel produced by cold single-roll drive rolling were investigated. By increasing the rolling deformation, the width of the grains decreased, and after 60% rolling, highly elongated ferrite grains and shear bands occurred in the microstructure. With the increase in the strain, first, the shear texture and then the deformation texture were strengthened in the samples. Dislocation density increased with increasing strain, which led to increasing the macro and microhardness. Also, the up and down surfaces of the sample had different hardness values due to being exposed to two rolls with different speeds. The 60% rolled sample had the highest yield strength (823 MPa), the highest ultimate tensile strength (833 MPa), and the lowest ductility (10.7%), which was due to increasing dislocation density and shear bands. After 60% rolling, the number, size, and depth of dimples decreased compared to the initial steel. However, the fracture mode of all deformed samples was ductile.