Oxidation resistance and phase constituents in the brazing interface of WC-TiC-Co hard alloys

摘要

The oxidation resistance and phase constituents in the brazing interface of WC-TiC-Co hard alloys have been researched by means of brazing inside a furnace, the scanning electron microscope (SEM) and the X-ray diffraction test, etc. The test results have indicated that a brazing joint in which the interface combines excellently can be obtained by using Cu-Zn-Ni brazing filler alloy, and controlling the heating temperature to 940-960 deg C and the holding time 10-15 min employing a suitable post-heat measure. The interface of the hard alloy and the brazing filler alloy is in a good condition. The interface zone consists of WC, TiC, and CuZn (alpha-phase). There are no micro-cracks, inclusions, etc., near to the brazing interface. The interface zone is formed by the mutual diffusion of elements in the hard alloy and the brazing alloy under the condition of high temperature.