Seamless Joining of ZTA Ceramics Without the Application of Pressure

Seamless joining of zirconia-toughened alumina (ZTA) ceramics without the application of any external pressure was demonstrated in this work through a reaction-bonded aluminum oxide (RBAO) method. Reliable joining of ZTA ceramics in a green-state was successfully accomplished in ambient air at 1600 degrees C for 2 h with the use of an Al/3Y-ZrO2/Al2O3 powder mixture as joining interlayer. The joining mechanism was discussed based on the RBAO process where the effective joining principally relies on the conversion of all Al particles to alumina. Thermogravimetry and differential thermal analysis confirmed the oxidation behavior of the milled Al particles. The joining interface exhibited excellent compositional and structural homogeneity without defects in commensurate with parent bodies. The mechanical properties of the joints were nearly equivalent to bare ZTA ceramics. This proposed simple and cost-effective joining technique can be used for the joining of other aluminabased advanced ceramics to realize large and complex-structures.