The diffusivity in α-type material was studied at 160 to 430C, under a pressure of 1atm., using absorption methods. The results could be described by:

D (cm2/s) = 2.38 x 10-3 exp[-2.34(kcal/mol)/RT]

at 160 to 340C, and by:

D (cm2/s) = 8.05 x 10-4 exp[-2.26(kcal/mol)/RT]

at 270 to 430C.

K.T.Kim, J.K.Park, J.Y.Lee, S.H.Hwang: Journal of Materials Science, 1981, 16[9], 2590-6