Determination of the diffusion reaction coefficient

Physicochemical interaction at the MnSi1.71–1.75/Mo interface

“…Table 3 lists the diffusion parameters of a Mo 1 -x Mn x Si 2 layer at temperatures from 970 to 1170 K. The temperature dependent rate constant k for the growth of the Mo 1 -x Mn x Si 2 k phase was determined under the assumption that the thickness of the layer of the intermetallic phase was a parabolic function of diffusion time: k = Δx/τ 1/2 [10], where Δx is the thickness of the layer and τ is the heat treat ment time. Using data obtained as described by Arza masov [11], we evaluated the diffusion coefficients (D) of manganese, molybdenum, and silicon in this phase at 1170 K by the formula D = k 2 C/(2ΔC), where С is the average of the concentrations at the two boundaries of the layer and ΔC is the difference between these concentrations. It is seen that the highest diffusion mobility is exhibited by Mo and Si, the lightest component.…”