Published online by Cambridge University Press: 21 February 2011
Interfacial reactions between either copper or titanium and cordierite-based (2MgO.2Al2O3.5SiO2) ceramic substrates are probed using X-ray Photoelectron Spectroscopy (XPS). Room temperature reactions are found to be strongly dependent on interfacial chemistry; while copper reacts weakly with the cordierite surface, titanium strongly reduces the Si-O and Al-O substrate bonds. Behavior during subsequent “in situ” annealing is dependent on substrate morphology. On amorphous cordierite films copper remains nonreactive while titanium dissociates remaining Si-O and Al-O bonds, forming a low valency Ti1+ oxide. On crystalline cordierite substrates copper diffuses rapidly upon annealing while titanium reduces substrate bonds forming a high valency Ti3+ oxide. Furthermore, thin 5Å Ti interlayers prevent copper diffusion at temperatures below 650°C. This study represents the first comprehensive treatment of the interfacial reactions in metal-multicomponent ceramic systems.