EFFECT OF NITROGEN AND SULFUR ON THE SEGREGATION OF MOLYBDENUM ON SINGLE-CRYSTALLINE FE3.5-PERCENT-MO-N,S ALLOYS

This work describes an experimental study of the effects of nitrogen a nd sulphur on the surface segregation of molybdenum in an Fe-3.5%Mo al loy. It is found that the presence of small concentrations of bulk dis solved nitrogen induce a strong synergetic segregation (cosegregation) of molybdenum and nitrogen. This effect is strongest for the (100)-or iented alloy, where an epitaxially stabilized MoN surface compound is formed. The synergetic effect of segregated sulphur on the segregation of molybdenum is found to be rather weak. This finding is consistent with the recent work of A. Rolland, M.M. Montagono, J. Cabane, Surf. S ci. 352-354 (1996) 206. (C) 1998 Elsevier Science B.V. All rights rese rved.