ORIENTATION-DEPENDENT SURFACE SEGREGATION OF ANTIMONY ON NONORIENTED ELECTRICAL STEEL SHEET

The surface segregation of antimony was studied using AES on a 1.8% Si steel alloyed with different mass contents of Sb (0.052 and 0.1%). The dependence of surface segregation on grain orientation and on the presence of other solute atoms (S, P, C, Al, Si) were investigated under UHV conditions in the temperature range from 450 to 900-degrees-C. The results lead to an explanation for the formation of a texture rich in (100)-grains in Si steel caused by the presence of Sb. Also grain boundaries were analysed by AES after annealing at 850, 700 and 550-degrees-C for different times. Since the grain boundary segregation was negligible one can conclude that the texture formation results from orientation dependent surface segregation of Sb causing differences in surface energies and stabilities of different grains.