The quasi-binary Al2O3/Mn3O4system was studied in air at temperatures ranging from 1573 to 1773K. The diffusion couple consisted of a single crystal of Al2O3 in which the (012) plane of the trigonal lattice was in contact with sintered polycrystalline Mn2O3. Markers of Pt were placed at the original interface, and the interdiffusion coefficients were calculated by using the Matano-Boltzmann method. The results could be described by:

D (m2/s) 2.02 x 10-11 exp[-138(kJ)/RT]

at 8.8at%Al, and by:

D (m2/s) = 1.38 x 10-8 exp[-185(kJ)/RT]

at 25.2at%Al.

K.Atarashiya, R.Nagasaki, K.Nishida: Transactions of the Japan Institute of Metals, 1987, 28[12], 966-70