The order-disorder transformation in the body-centered cubic structure was investigated by a Monte Carlo method. A critical temperature was observed at the point $\left(\frac{v}{\mathrm{kT}}\right)=-0.315\mathrm{}$. The results of the calculation are in close agreement with the best analytical approximations. The calculated variation of order with temperature is in good agreement with experimental data on $\beta$ brass and $\beta$-AgZn. Some information on the kinetics of the transformation was obtained. It appears likely that the rate-limiting process for diffusion in the ordered structure is jumping of vacancies to second neighbor positions.

• Received 24 May 1961

DOI:https://doi.org/10.1103/PhysRev.124.54