The effects of Cr and Mn upon the cohesion of the γ-phase Σ = 11 [1¯10]/(11¯3) grain boundary were investigated, on the basis of the Rice-Wang thermodynamic model, by using first-principles density functional theory. The electronic properties were studied for the Cr/Fe and Mn/Fe systems. In these systems, the effect of Cr and Mn was to enhance the cohesion of the grain boundary; due to an anisotropic bonding which weakened the bonds in the grain boundary plane but strengthened those in planes which were perpendicular to the grain boundary. Structural relaxation was detrimental to the cohesion of the grain boundary. Overall, Cr acted as a cohesion enhancer and Mn acted as an embrittler.

Effects of Cr, Mn on the Cohesion of the γ-Iron Grain Boundary. R.Yang, D.L.Zhao, Y.M.Wang, S.Q.Wang, H.Q.Ye, C.Y.Wang: Acta Materialia, 2001, 49[6], 1079–85