Experimental data from the paste-boriding process during growth of a Fe2B layer were used to estimate the diffusion coefficient of B in Fe2B based upon a kinetic model obtained from the mass balance and considering thermodynamic equilibrium at the Fe2B/α interface during growth. The diffusivity of B in Fe2B, at between 1223 and 1323K, could be described by:

D (m2/s) = 1.311 x 10-6 exp[-151000(kJ)/RT]

Kinetic Study of Boron Diffusion in the Paste-Boriding Process. I.Campos, J.Oseguera, U.Figueroa, J.A.García, O.Bautista, G.Kelemenis: Materials Science and Engineering A, 2003, 352[1-2], 261-5