Microstructural characterization in diffusion bonded TiC-Al_2O_3/Cr18-Ni8 joint with Ti interlayer

摘要

Ceramic matrix composite, TiC-Al_2O_3, and stainless steel, Crl8-Ni8, were joined at 1400 K by solid state diffusion bonding, making use of a Ti foil acting as thermal stress relief interlayer. The microstruc-ture of the joint was thus formed. The diffusion bonded TiC-Al_2O_3Cr18-Ni8 joint was investigated by a variety of characterization techniques such as scanning electron microscope (SEM) with energy dispersion spectro-scopy (EDS) and X-ray diffraction (XRD). The results indicate that Ti foil is fully fused to react with elements from substrates and Ti_3Al, TiC and alpha-Ti are formed in the diffusion bonded TiC-Al_2O_3/Crl8-Ni8 joint. The interfacial shear strength is up to 99 MPa and the shear fracture occurs close to the ceramic matrix composite due to the application of Ti foil acting as thermal stress relief interlayer.