Diamond/WC-Fe-Ni composite is a potential composition for impregnated diamond drill bits. It is necessary to avoid the graphitization of the diamond from Fe and Ni under the powder metallurgy process. Boron carbide (B₄C) was coated on diamond, and diamond/WC-Fe-Ni composites were consolidated by hot pressing at different temperatures. The influences of sintering temperature and interfacial structure on bending strength and wear behavior were investigated. The bending strength for diamond/WC-Fe-Ni composite was dependent on matrix densification and interfacial graphitization. Un-coated diamond was eroded by Fe-Ni matrix and partially converted to graphite during the sintering process at all sintering temperatures. In opposite, B₄C coating was beneficial to matrix densification at a lower sintering temperature, and delayed the appearance of graphitization to around 1300 °C. Therefore, the diamond/WC-Fe-Ni composites with B₄C coating exhibited larger bending strength and better wear behavior at a relative low sintering temperature.

金刚石/ WC-Fe-Ni复合材料是浸渍金刚石钻头的潜在成分。必须避免在粉末冶金过程中由铁和镍形成的金刚石石墨化。将碳化硼（B ₄ C）涂覆在金刚石上，并通过在不同温度下进行热压使金刚石/ WC-Fe-Ni复合材料固结。研究了烧结温度和界面结构对弯曲强度和磨损行为的影响。金刚石/ WC-Fe-Ni复合材料的弯曲强度取决于基体致密化和界面石墨化。未涂层的金刚石在所有烧结温度下的烧结过程中均被Fe-Ni基体侵蚀，并部分转化为石墨。相反，B ₄C涂层在较低的烧结温度下有利于基体致密化，并且将石墨化的出现延迟至约1300℃。因此，在相对较低的烧结温度下，具有B ₄ C涂层的金刚石/ WC-Fe-Ni复合材料表现出更大的弯曲强度和更好的磨损性能。