Ortiz-Domínguez M, Zuno-Silva J, Keddam M, Damián-Mejía O, Elias-Espinosa M (2015). Diffusion model and characterization of Fe2B layers on AISI 1018 steel. International Journal of Surface Science and Engineering, online, http://www.inderscience.com/info/ingeneral/forthcoming.php?jcode=ijsurfse.
An approach was suggested to study the kinetics of formation of Fe2B layers grown at the surface of AISI 1018 steel by the pack-boriding process. The kinetic model considered the principle of mass conservation at the (Fe2B/substrate) interface to evaluate the boron diffusion coefficient of Fe2B in the temperature range of 1123-1273 K. Validation of the model was made by comparing the experimental Fe2B layer thickness with the predicted value for the borided sample at 1253 K during 5 h. In addition, the generated boride layers were analyzed by optical microscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction analysis. Finally, a contour diagram describing the evolution of Fe2B layer thickness as a function of treatment time and temperature was also proposed. Finally, the boron activation energy for AISI 1018 steel was estimated as 159.3 kJ mol-1 basing on our experimental results.