Promoting the bonding strength and abrasion resistance of brazed diamond using Cu-Sn-Ti composite alloys reinforced with tungsten carbide

摘要

Diamond brazing is widely used in manufacturing wear-resistant tools. However, designing Cu-based filler metals with good welding characteristics and excellent mechanical properties remains a challenging task. In this work, diamond particles were connected to Q460 steel by using Cu-Sn-Ti composite fillers reinforced with different contents of micron-scale tungsten carbide (WC) particles. The microstructure of the brazing interface was analyzed via scanning electron microscopy and energy dispersive spectroscopy. The phase constitution of the brazed seam was characterized via X-ray diffraction. The effects of adding reinforcement on the mechanical properties of the vacuum brazed diamond samples were comprehensively analyzed and discussed. Results showed that the connection between diamond particles was effectively promoted by the addition of 15 wt% WC particles to the Cu-Sn-Ti fillers. The diamond and steel matrix were closely connected because of the formation of TiC and Cu-Ti compounds. Samples with 15 wt% WC had a higher shearing strength and a lower abrasion loss than samples with different WC contents. Morphological examination of the wear surface showed that the interface reaction between WC and Cu-based filler alloys was tightly connected. Reinforcement with WC effectively improved the bonding strength and wear resistance of the samples.