COMPUTER-SIMULATION OF TRACER CORRELATION-EFFECTS IN ORDERED ALLOYS WITH THE B2 STRUCTURE

Tracer diffusion via the agency of vacancies in a b.c.c. binary ordered alloy was simulated using a Monte Carlo method. Tracer correlation factors and the average cosines of the angle between the first tracer jump and the second were calculated in an averaged sense (irrespective of sublattice), as well as in a sublattice sense according to the suggestion of Bakker (1979, Phil. Mag. A, 40, 525). It was found that the results for the correlation factors were considerably lower than those of an earlier Monte Carlo study by Bakker and coworkers and in general the fit to Bakker's analytical results deteriorated. Bakker's suggestion of partitioning the correlation factor into sublattice components is generally found to be a better approximation than attempting to calculate this quantity using average cosines irrespective of sublattice.