Microstructure and XRD analysis in the brazing zone of a new WC–TiC–Co hard alloy

The microstructure and phase constituent near the brazing interface of a new WC–TiC–Co hard alloy was investigated by means of a scanning electron microscope, X-ray diffraction and an electron probe microanalysis. Test results indicated that the brazing joint with the interface combined excellently and can be obtained by using a Cu–Zn–Ni brazing filler alloy and by controlling the technology parameters. The microstructure of the brazing filler alloy is α+β eutectic. The brazing interface consists of WC, TiC, CuZn (α phase), and α-Co phase. There are no micro defects (such as microcracks, inclusions, etc.) near the interface.