Joining and mechanical testing of oxide/oxide (NextelTM 610/alumina-zirconia) ceramic composites

Efficient joining materials and techniques are of critical importance for the integration of CMCs in high performance structures. Continuous oxide fiber Nextel TM 610/alumina-zirconia composites were successfully joined to themselves by using a novel glass-ceramic based on the SiO 2 -CaO-Al 2 O 3 -MgO-Y 2 O 3 -ZrO 2 system. Crystallization kinetic of the novel glass-ceramic was studied using Matusita, Sakka and Ozawa equations. Single lap off-set shear tests and four-point bending tests were performed at room temperature and at 850 °C to investigate the mechanical strength of the joints. Thermal ageing was performed at 850 °C for 100 h in air to check the thermal stability of the joined components. The results showed that the joints were oxidation resistant and the joined interfaces were well bonded. Single lap off-set shear tests on joined samples resulted in delamination of the composites. The average flexural strengths of the joined samples were 71 MPa and 81 MPa, at room temperature and at 850 °C, respectively.