Active metal brazing of zirconia

Active metal brazing is a well-established technique for the joining of ceramics to themselves and to metals. Extensive studies have been reported in the literature which examine the interfacial reactions and thermodynamics occurring between the braze alloy and ceramic. In this work, the interactions between Ag-Cu-Ti based braze alloys and partially stabilised zirconia have been examined. During brazing, the active element (titanium) reacts with the zirconia, depleting the surface region of oxygen. This manifests itself as a discolouration - darkening the zirconia. This phenomenon and how it affects the properties of zirconia forms the basis of this work. (C) 2000 Acta Metallurgica Inc. Published by Elsevier Science Ltd. All rights reserved.