The bulk and grain-boundary diffusion of 14C was studied by using the radio-tracer and serial sectioning technique. The B and C kinetic regimes were operative for grain-boundary diffusion at 800 to 1173K. It was found that the values of P (= sδDgb), Dgb and s obeyed the Arrhenius dependences:

973–1173K:     P (m3/s) = 5.15 x 10-15 exp[-83.1(kJ/mol)/RT]

800–950K:     Dgb (m2/s) = 2.3 x 10-6 exp[-133.0(kJ/mol)/RT]

s = 4.7 x 100 exp[-49.9(kJ/mol)/RT]

B.Bokstein, I.Razumovskii: Interface Science, 2003, 11[1], 41-9. See also: Defect and Diffusion Forum, 2003, 216-217, 123-32