Formation mechanism of orange peel defects in low carbon deep drawing steel sheets

Taking batch annealed SPCD steel sheets as an example, orange peel defects in the surface of sheet stamping concerning with their formation mechanism and dependence on grain orientation were investigated by means of SEM, XRD and electron backscatter diffraction (EBSD) techniques. The results show that the orange peel defects are resulted from excessively coarse ferrite grains, whereas weak favorable 111 texture and a larger stamping value might be the key factors aggravating the formation of orange peel defects. Different morphologies featured by smooth and rough zones on the free surface of orange peel do not show remarkable dependence on grain orientation, and both display orientation feature with dominant 112〈110〉 and 111〈110〉 textures. The surface contact condition plays an important role in the surface morphology.