Simulation of the Growth Kinetics of FeB and Fe2B Layers on AISI D2 Steel by the Integral Method

Resumo

In the present study, a new diffusion model based on the integral method was suggested to investigate the boriding kinetics of pack-borided AISI D2 steel. This diffusion model considered the effect of boride incubation time of the total boride layer (FeB + Fe₂B). Firstly, the diffusion coefficients of boron in the FeB and Fe₂B layers were estimated using a simple approach derived from the integral method. Secondly, the values of boron activation energies for the FeB and Fe₂B layers were determined and compared with the literature data. The formulated diffusion model has been validated by using additional boriding conditions. The total boride layer thicknesses, obtained experimentally at 1243 K for 2, 4 and 6 h, were compared to the predicted thicknesses. Finally, a good agreement was observed between the experimental and the predicted results.