Effect of transverse pre-stretching before deep drawing on the surface ridging resistance of 17%Cr ultra-purified ferritic stainless steel

Cup-drawing test was performed to study the effect of transverse pre-stretching, namely 3%, 6%, 9% and 12% deformation, on the surface ridging resistance during deep drawing of a 17% Cr ultra-purified ferritic stainless steel cold-rolled annealed sheet. The evolution of textures and grain clusters in the tested sheet after transverse pre-stretching was analyzed by electron back-scatter diffraction and X-ray diffraction. It is found that the ridging resistance apparently improves after the 9% transverse pre-stretching. Because the content of 001 〈uvw〉 orientation grains is not enough to meet the requirement of the Chao ridging model, this model is not suitable for ridging of the tested sheet. However, the Takechi model, which is called an out-of-plane shearing strain model, is considered to be suitable for ridging of the tested sheet. It is concluded that the narrow of the width of γ-fiber texture clusters and the deflection of grain clusters to the rolling direction are the major causes of improving the ridging resistance.