Microstructure and mechanical properties of vacuum brazed CBN abrasive segments with tungsten carbide reinforced Cu–Sn–Ti alloys

In this study, cubic boron nitride (CBN) abrasive segment specimens were produced via high vacuum brazing using Cu-Sn-Ti composite alloys containing tungsten carbide reinforcing particles. The specimen microstructures and interfacial analysis of the brazed CBN grain were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray diffraction (XRD). The mechanical properties of hardness, wear resistance, and three-point bending strength of the fabricated specimens were tested. The specimen shape brazed using the composite Cu-Sn-Ti alloy was better than that of the specimen brazed using the pure Cu-Sn-Ti alloy. TiN and TiB2 phases were maintained between the brazed CBN and composite alloys. Meanwhile, TiC compounds were generated between the alloys and WC particles. The hardness of the specimens increased with increasing WC particle content. However, the S25 specimen containing 25 wt% WC particles, exhibited the highest wear resistance and bending strength, increasing by 26.5% and 25.6%, respectively, compared with those of the CBN segment specimen brazed using pure Cu-Sn-Ti alloy. This study provides strategies for developing multilayer brazing CBN abrasive tools.