The interdiffusion coefficients of the refractory elements in the Fe-Cr-X (X = Mo, W) and Fe-Mo-W ternary alloys were measured by using the modified Boltzmann-Matano method for ternary systems. The cross-interdiffusion coefficient, DCrWFe, was positive (table 7) in the Fe-Cr-W ternary alloy; indicating that W accelerated interdiffusion between Fe and Cr atoms. On the other hand, the cross-interdiffusion coefficient, DCrMoFe, was negative in the Fe-Cr-Mo ternary alloys (table 8); indicating that Mo suppressed interdiffusion between Fe and Cr atoms. In addition, the cross-interdiffusion coefficient, DWMoFe, was positive in the Fe-Mo-W diffusion system. This implied that Mo additions accelerated interdiffusion between Fe and W.

Interdiffusion of Refractory Elements in Fe-Cr-X (X-Mo, W) and Fe-Mo-W Ternary Iron Alloys. K.Takeda, K.Yamashita, Y.Murata, T.Koyama, M.Morinaga: Materials Transactions, 2008, 49[3], 479-83

Table 7

Interdiffusion Coefficients in the Fe-Cr-W System at 1523K