In this paper, the reactive diffusion in Ni80C20r?Ti ternary system is discussed at 1173K. The couple was prepared and annealed for 100 h. two intermetallic phases two-phase zones occurred, namely: Ti2Ni, TiNi, TiNi+Cr, TiNi3+Cr. Based on experimental results (molar fractions, thicknesses of phases), intrinsic coefficients all components each phase were numerically approximated. Wagner method u...