The O self-diffusion behavior in deformed sapphire single crystals containing a high density of unidirectional basal dislocations was examined at 1424 to 1636C using 18O isotopes and secondary ion mass spectrometry depth profiling. The pipe and lattice diffusion kinetics were best described by:

r2D(m4/s) = 4.6 x 10-20exp[-4.8(eV)/kT]

and

D(m2/s) = 2.9 x 10-1exp[-5.5(eV)/kT]

respectively.

T.Nakagawa, A.Nakamura, I.Sakaguchi, N.Shibata, K.P.D.Lagerlöf, T.Yamamoto, H.Haneda, Y.Ikuhara: Journal of the Ceramic Society of Japan, 2006, 114[1335], 1013-7