Atomic diffusion by the dumb-bell mechanism in a concentrated random bcc alloy

Matter transport by <110> dumb-bell interstitials in the bcc random alloy is considered in an analytical treatment based on linear response theory. Four different jump mechanisms of the dumb-bell are dealt with. It was found that at a low level of approximation relations can be deduced which give two of the three phenomenological coefficients in terms of the third one. (These relations are analogous to exact ones deduced for vacancy diffusion in the random alloy by Moleko, L. K., and Allnatt, A. R., 1998, Phil. Mag. A, 58, 666). Monte Carlo simulation shows that the relations are quite accurate, suggesting that they may well be exact.