The effect of composition and temperature upon Ni bulk self-diffusion was studied in monocrystalline specimens, having well-defined compositions which ranged from 36.8 to 56.6at%Ni, at 1050 to 1630K. The data could be described by:

46.8at%Ni:     D (m2/s) = 2.34 x 10-5 exp[-2.97(eV)/kT]

48.7at%Ni:     D (m2/s) = 2.39 x 10-5 exp[-2.97(eV)/kT]

49.7at%Ni:     D (m2/s) = 1.67 x 10-5 exp[-2.92(eV)/kT]

50.0at%Ni:     D (m2/s) = 2.98 x 10-5 exp[-2.99(eV)/kT]

51.8at%Ni:     D (m2/s) = 4.80 x 10-5 exp[-2.99(eV)/kT]

54.6at%Ni:     D (m2/s) = 4.36 x 10-5 exp[-2.88(eV)/kT]

56.6at%Ni:     D (m2/s) = 1.03 x 10-6 exp[-2.39(eV)/kT]

The diffusion penetration profiles of Ni were determined by using 2 different techniques of profile detection. Radiotracer experiments were carried out by using 63Ni tracers, serial sectioning techniques; and a sensitive liquid scintillation counter at high temperatures. At lower temperatures, the diffusion profiles were analyzed by using secondary ion mass spectrometry and the highly enriched stable isotope, 64Ni.

S.Frank, S.V.Divinski, U.Södervall, C.Herzig: Acta Materialia, 2001, 49[8], 1399–411