Impurity diffusion of Al in Ni single crystals studied by secondary ion mass spectrometry (SIMS)

Secondary ion mass spectrometry (SIMS) is used to study the impurity diffusion of Al in Ni single crystals over a temperature range from 914 to (1212) K. The high affinity of Al for oxygen results in some unusual behaviour during SIMS analysis (i.e. instability of the Al background and Ni matrix signals), but arguments presented in the present paper lead to the conclusion that the effect of this behaviour on the measurement accuracy is small. The values obtained for the impurity diffusion activation energy and pre-exponential factor are Q = (260 ± 13) kJ/mol and D0 = (1.0 ± 3.4) cm2/s, respectively. These values are in good agreement with data obtained by other techniques.