The impurity diffusion of Au was investigated by using the radio-tracer serial-sectioning technique, and the high specific activity isotope: 195Au. Measurements were carried out at temperatures ranging from 618 to 1036K and from 450 to 526K in the Harrison type-B and type-C regimes, respectively. In the former, the product of the segregation factor, the grain boundary diffusion coefficient, and the grain boundary width was determined (table 37). In the latter regime, the grain boundary diffusivities were measured directly. By combining the 2 sets of values, and assuming a grain boundary width of 0.5nm, the segregation factor was evaluated. From the temperature dependence of the latter, a segregation enthalpy of -9.7kJ/mol was obtained.

T.Surholt, J.M.Mishin, C.Herzig: Physical Review B, 1994, 50[6], 3577-87

Table 37

Product of the Segregation Factor, Grain Boundary Diffusion

Coefficient, and Grain Boundary Width, for Au in Cu