A MODEL FOR COUPLED GROWTH OF REACTION LAYERS IN REACTIVE BRAZING OF ZRO2-TOUGHENED AL2O3

in the present investigation, process modelling techniques have been a pplied to describe coupled reaction layer growth in reactive brazing o f ZrO2-toughened Al2O3 with Ag-Ti filler metals, The model takes into account both the successive evolution of the titanium oxide layer at t he ceramic/braze metal interface at elevated temperatures and the subs equent decomposition of the reaction products during cooling. The resu lts are presented in the form of novel process diagrams which illustra te in a quantitative maimer the microstructural connections throughout the various stages of the process. The diagrams can, in turn, be used to calculate the individual reaction layer thicknesses at room temper ature and relate these directly to the content of-reacting element in the braze alloy.