Interfacial Microstructure and Reaction Phases in Si_3N_4/Si_3N_4 Joints Brazed with Cu-Zn-Ti Filler Alloy

摘要

Si_3N_4 ceramic was jointed to itself using (CuZn)85Ti15 filler alloy at 1123-1323 K for 0.9 ks. TEM observation showed that a reaction zone of TIN and/or Ti_2N exists at the interface between the ceramic and filler alloy. When the brazing temperature is lower than 1223 K, the interfacial reaction zone is mainly composed of Ti_2N, which has cylindrical shape and is randomly orientate in the zone. There is a crystal orientation relationship between the Ti_2N in the reaction zone and the Cu in the Cu-Zn solid solution, which is: {110} _(Ti2N)//{420}_(Cu),<001>_(Ti2N)//<001>_(Cu). When the brazing temperature is higher than 1223 K, the interfacial zone is composed of TiN, which has plate shapes crossing each other.