Inhomogeneity of Thickness of Sheet in Different Forming Path

By making use of low-carbon steel K08Al, 08Al, the change of surface roughness Rz,Rm value according to the forming paths of uniaxial, plane, biaxial, uniaxial-biaxial and biaxial-uniaxial deformation models was investigated. The initial value f_o and the change of inhomogeneity of thickness f_R with strain were measured. The results show that the surface roughness Rz, Rm increase linearly with the increase of strain while inhomogeneity of thickness f_R decrease in each forming path.