ABSTRACT

The interlayer defects of diamond/copper (Cr) composite have been eliminated by adding holmium (III) oxide through Spark Plasma Sintering (SPS) method. The effects of Ho₂O₃ addition of diamond–copper interlayer on the microstructure and phase composition are investigated. The total density of states (DOS) and partial density of states (PDOS) are investigated by the first-principles calculations. It is revealed that the addition of Ho₂O₃ has a distinct modification effect on diamond–copper _(Cr) interlayer. Obvious cracks around the diamond outer surface are hardly found, and the diamond particles are enfolded by the copper matrix. The Cr₂C phase that beneficial to reduce interlayer defects and improve interlayer bonding was generated under the effect of adding Ho₂O₃. The thermal conductivity of diamond/copper _(Cr-Ho2O3) is 686 W/(m·K). The possible reasons for doping Ho₂O₃ to eliminate interlayer defects and improve the thermal conductivity were discussed.

摘要

通过火花等离子烧结（SPS）方法添加氧化钬（III），消除了金刚石/铜（Cr）复合材料的层间缺陷。研究了Ho ₂ O ₃添加金刚石-铜夹层对微观结构和相组成的影响。通过第一性原理计算研究了总态密度 (DOS) 和部分态密度 (PDOS)。结果表明，Ho ₂ O ₃的加入对金刚石-铜_（Cr）夹层有明显的改性作用。金刚石外表面几乎没有明显的裂纹，金刚石颗粒被铜基体包裹。铬₂在加入Ho ₂ O ₃的作用下，生成了有利于减少层间缺陷和改善层间结合的C相。金刚石/铜_{（Cr-Ho2O3）}的导热系数为686 W/(m·K)。讨论了掺杂Ho ₂ O ₃以消除层间缺陷和提高热导率的可能原因。