Tracer Diffusion of Ni and Ge in L1_2-Type Intermetallic Compound Ni_3Ge

摘要

The diffusion coefficients of ~(63)Ni and ~(68)Ge in Ni_3Ge with three compositions from 23.2 to 24.5 at.% Ge have been measured by the conventional radioactive tracer technique in the temperature range from 1064 to 1323 K. The diffusion coefficient of Ge at 1223 K, for example, is from 100 to 300 times smaller than that of Ni. The diffusion coefficient of Ni is almost independent of composition, whereas that of Ge decreases with increasing the concentration of Ge towards the exact stoichiometry. On the basis of the experimental data, the mechanism of diffusion is discussed.