ABSTRACT
Diffusion controlled transformation simulations of carbon steel/nickel diffusion couple were performed and the results were compared with the experimental results previously reported, which show that the interdiffusion of Fe and Ni atoms occur and the hard layer forms around the bonding interface at two step heating. The simulation was divided into two heating steps. It was shown that the interdiffusion of Fe and Ni atoms occur at the first step heating (1250°C) and the carbon concentrated layer forms after the second step heating (600-800°C) at the carbon steel side near the interface, where Ni atoms diffuse from the nickel at the first step heating. The agreement between the simulation and the experimental results is good. The formation of the carbon concentrated layer is affected by the cementite precipitation in the carbon steel.