Abstract
The impurity diffusion coefficient of tin in γ-iron has been determined by the serial sectioning method with the radioactive tracer 113Sn in the temperature range between 1197 and 1653 K. The temperature dependence of the diffusion coefficient shows the linear Arrhenius relationship, expressed by
D=(0.845−0.119+0.141)×10−4exp[−(261.7±1.8)kJmol−1⁄RT]m2s−1.
The magnitudes of both the frequency factor and the activation energy can be regarded as normal. The anomalously low values obtained by the previous workers appear to be due to enhanced diffusion through short circuiting paths such as grain boundaries and dislocations and by impurities contained in their iron specimens.
