Interfacial Behavior and Low‐Temperature Brazing Performance of Brazed Diamond with Ni–Cr‐Based Filler

Due to the high brazing temperature and catalytic action of catalyst element Ni, the brazed diamond with Ni–Cr filler alloy is prone to severe thermal damage, thereby resulting in premature interface failure between diamond and filler alloy. In this work, the interface bonding behavior and mechanism, as well as joint performance of brazed diamond with Ni–Cr filler doped with Cu, are systematically investigated through multiscale simulations and experiments. The results show that the mixing of Cu effectively adjusts the ductility of brazing layer and refines the carbides on diamond surface, thereby reducing the residual stress and thermal damage of diamond. Additionally, the mixing of Cu also facilitates a sufficient reaction between Cr and C at the interface, thus improving the interface bonding strength between Ni–Cr filler and diamond. Notably, the machining performance of brazed diamond samples with Ni–Cr filler doped with 10 wt% Cu–Sn–P alloy is significantly enhanced at the low brazing temperature of 1010 °C. The results provide a novel insight to clarify the interface action mechanism and realize the low‐temperature brazing of diamond through the composition optimization of Ni–Cr filler based on multiscale feature fusion.