Interaction of Si3N4 with titanium at elevated temperatures

In relation to the joining of silicon nitride ceramics to metal, the reaction products and the reaction mechanism between Si3N4 and titanium have been investigated under a nitrogen or an argon atmosphere at temperatures of 823-1573 K. Using Si3N4/titanium powder mixtures, reaction rates were determined by thermogravimetric (TG) analysis, and reaction products were examined by X-ray diffraction. At higher temperatures and on prolonged heating, reaction products were changed in the following orders: TiN2, TiN2 + TiN, TiN + TiSi2 + Si, TiN + Si and TiN (nitrogen atmosphere) and TiN2 + Ti5Si5, TiN2 + TiN + Ti5Si3 and TiN + TiSi2 + Si (argon). By relating these results to TG measurements, a full understanding of the reaction mechanism between Si3N4 and titanium was acquired.