An investigation of springback stresses in AISI-1010 deep drawn cups

The residual stresses created by deep drawing of AISI-1010 cups were investigated by means of neutron diffraction. The wall thickness of the cups was below 3.0 mm, for which 8-10 through-thickness measurements were conducted. It was found that the axial, and tangential stress profiles are similar to what is expected from a bending-unbending operation, but it also exhibits a strong dependence on the axial and, to a minor extent, on the circumferential position. The strong axial stress dependence reflects the effect of stretching while the weaker circumferential stress variations are due to sheet anisotropy. We also found that the thermal relief of cold work in the initial AISI-1010 cold rolled blank has no discernable effect both on the residual stresses and the springback.