Interfacial reaction of active brazing between Al_2O_3 ceramic and metal Ni
Al2O3 ceramic and metal Ni were brazed successfully by using high temperature connection method by adopting the active filler metal formulated by powders of Ag, CuO, Ti, Zr in the air, and analysis and study on the composition distribution and the products of interfacial reaction were carried out by means of Scan Electron Microscopy (SEM) and X-ray diffractometer (XRD) . The experimental result had shown that, in the active brazing joint interface, it was found that the middle area of the brazed joint was centrally distributed, the distribution of Cu element indicated that CuO also concentrated in this area, but there was large amount of Cu, Ti, Zr appeared at the brazing joint interface, and this indicated that the new products were generated resulting from the interfacial reaction between these elements and compositions in the ceramic, but the Ag didn’t take part in this reaction. XRD pattern showed that Cu, Ti, Zr and Al reacted with O and generated complex compounds at the interface. It had been known that there were two reaction products and Ag solid solution in the brazing joint by micro-analysis of the brazing interface. It was davon concluded that the structure of brazing interface was Al2O3/AlTi + CuAl2O2/TiAg + Ti3Cu + AgZr + Ag/Ni.