Ordering Kinetics In An Fcc A(3)B Binary Alloy Model: Monte Carlo Studies

Using an atom-vacancy exchange algorithm, we investigate the kinetics of the order-disorder transition in an fcc A(3)B binary-alloy model following a temperature quench from the disordered phase. We observe two clearly distinct ordering scenarios depending on whether the final temperature T-f falls above or below the ordering spinodal T-sp, which is deduced from simulations at equilibrium. For shallow quenches (T-f>T-sp) we identify an incubation time tau(inc) which characterizes the onset of ordering through the formation of overcritical ordered nuclei. The algorithm we use together with experimental information on tracer diffusion in Cu3Au alloys allows us to estimate the physical time scale connected with tau(inc) in that material. Deep quenches, T-fMore