The influence of chemical interactions between metallic and metalloid solutes on their segregation in α-Fe II: SbM (M ≡ 3d transition metal) pair interactions in monoantimonides and in α-Fe solid solution from techniques of solid state physics

Abstract

Antimony solubility limits in α-Fe doped with 3d metals were measured by 121Sb Mössbauer spectroscopy and X-ray diffraction. MSb pair interactions in the monoantimonides MSb were calculated from a simple model using a regular solution approximation. They were found to be largest for M ≡ Ti, Mn, Ni and smallest for M ≡ Cr, Co. SbM pair interactions in α-Fe solid solution for M ≡ Ti, Cr, Co, Ni were also investigated directly by measurements of residual resistivity and nuclear magnetic resonance of antimony and cobalt nuclei. Again, SbTi and SbNi pair interactions were found to be large compared with SbCr and SbCo interactions. The deduced interactive behaviour between antimony and transition elements in bulk phases, i.e. dilute solid solution and concentrated compounds, is in quantitative agreement with the results obtained at the free surface and reported in Part I. The electronic structure of the 3d elements is concluded to be the parameter primarily responsible for these interactions, rather than the concentration range, crystal structure or other related parameters. The metallurgical signifacance of the results is discussed.