Application of proton activation techniques for studying diffusion in oxides

Activation analysis can be used for the study of self-diffusion in oxide ceramics. A method employing the 18O(p,n)18F reaction in combination with the detection method for 18F was proposed. An other method, for example 18O(p,α)15N reaction, appears to have universal applicability for studying oxygen diffusion. The reaction product can be detected and converted into 18O concentration. Since the energy of alpha particles can be correlated with the depth beneath the surface at which the reaction occurred, the non-destructive determination of 18O profile can be achieved in single proton irradiation by alpha particle spectrometry. This method permits the study of both the diffusion coefficient and the kinetics of surface exchange reaction. Possible surface and near-surface effects can come under close scrutiny, and diffusion coefficients as low as 10-17 cm2/sec can be measured readily. (Kato, T.)