XPS and SIMS examination of alumina fibres affected with Mg and MgLi melt

Fibre/matrix interfaces in delta-Al2O3/Mg8Li and delta-Al2O3/Mg composites have been investigated using XPS and SIMS analysis of extracted delta-Al2O3 fibres in context with previous XRD observations. Results obtained indicat e that in MgLi based composites lithium enters preferentially the interfaci al redox reactions producing Lif ions that occupy vacant cation positions i n the defect delta-Al2O3 lattice which results in a strong fibre/matrix int erfacial bond. On the other hand, in Mg matrix composites the magnesium oxi de appears to be the final reaction product that does not enter the solid s tare reaction with adjacent delta-Al2O3 fibre during the melt infiltration process, so that only relatively weak interfacial bond is created.