The effective diffusion coefficient of boron in the Fe2B layers formed on the iron substrate

In this current work, the boron diffusion coefficient in Fe2B was firstly evaluated using a diffusion model. It considers the effect of the incubation times required to form the Fe2B layers by the paste-boriding process on the iron substrate. This model solves the mass balance equation at the (Fe2B/substrate) interface under certain assumptions. Afterwards, the effective boron diffusion coefficient in Fe2B was evaluated through an application of a simple equation. As a result, the estimated value of boron activation energy in the presence of chemical stresses was found to be equal to 146.5 kJ mol(-1) on the basis of experimental data taken from the literature.