金刚石表面改性及基体合金化对金刚石/铜复合材料导热性能的影响

以Pr₆O₁₁为刻蚀剂表面粗糙化处理金刚石颗粒，采用放电等离子烧结技术制备了金刚石/铜（硼）复合材料（金刚石体积分数为60.0%，硼体积分数为0.3%），通过试验、热流密度模拟和声子谱计算研究了金刚石表面改性及基体硼合金化对金刚石/铜复合材料导热性能的影响。结果表明，粗糙化的金刚石界面增加了接触面积；在基体中添加硼元素，复合材料在烧结后出现B₄C相，B₄C相的形成改善了金刚石–铜两相界面结合状态。金刚石粗糙化与基体合金化两者的共同作用有效减少了界面热阻，优化了热通量传递的效率，提高了复合材料的导热性能。金刚石/铜复合材料热导率从421 W·m?1·K?1提高到了598 W·m?1·K?1，提升了近42%。

Effects of diamond surface modification and matrix alloying on the thermal conductivity of copper/diamond composites

Diamond particles were roughened with Pr₆O₁₁ as the etching agent, and the diamond/copper (boron) composites with the diamond volume fraction of 60.0% and the boron volume fraction of 0.3% were prepared by spark plasma sintering. The effects of diamond surface modification and matrix boron alloying on the thermal conductivity of the diamond/copper composites were investigated by the experiments, thermal flux simulations, and phonon density of states. The results show that, the roughness of the diamond interface increases the contact area; the B₄C phases appear after the sintering when the boron element is added in the matrix, and the formation of the B₄C phases improves the bonding state of the diamond?copper interface. The interaction of diamond roughness and matrix alloying can effectively reduce the interfacial thermal resistance, optimize the efficiency of heat flux transfer, and improve the thermal conductivity of composites. The thermal conductivity of diamond/copper composites increases from 421 W·m?1·K?1 to 598 W·m?1·K?1, increasing by nearly 42%.