基体中Ti元素含量对金刚石/Cu-Ti复合材料热导率的影响

采用真空热压法制备了金刚石体积分数为63%的金刚石/Cu-Ti复合材料，研究了基体中Ti含量对金刚石/Cu-Ti复合材料界面显微结构和热导率的影响。随着Ti含量的增加，金刚石/Cu-Ti复合材料热导率先增加后减小。当基体中Ti含量为1.1wt%时热导率最高，为511 W/（m·K）。Ti含量小于1.1wt%时，烧结过程中两相界面间生成的碳化物数量和面积随Ti含量的增加而增加，优化了界面结合，提高了界面结合强度，增加了界面传热通道数量，使金刚石/Cu-Ti复合材料导热性能提高。Ti含量的增加同时伴随着碳化物热阻增加和基体导热性能的恶化。过量的Ti元素使低导热性能的碳化物层厚度增加，碳化物层本身热阻增加，界面热导降低，金刚石/Cu-Ti复合材料导热性能下降。

Influence of minor Ti addition in matrix on the thermal conductivity of Diamond/Cu-Ti composites

The 63vol% Diamond/Cu-Ti composites were prepared by vacuum hot pressing. The influence of minor Ti addition on the interfacial microstructure and thermal conductivity of Diamond/Cu-Ti composites was studied. The thermal conductivity of Diamond/Cu-Ti composites first increases and then decreases with increasing Ti contents. The maximum value of 511 W/(m·K) is obtained at 1.1wt%Ti. When Ti contents are less than 1.1wt%, the number and area of carbides generated during the sintering process increase with the increase of Ti content, the interface bonding is optimized, the interface bonding strength is improved, the number of interface heat transfer channels is increased and the thermal conductivity of Diamond/Cu-Ti composites is improved. The increase of Ti content is accompanied by the increase of carbide thermal resistance and the deterioration of the thermal conductivity of the matrix. The excess Ti element increases the thickness of the carbide layer with low thermal conductivity, increases the thermal resistance of the carbide layer itself, reduces the interfacial thermal conductivity, and decreases the thermal conductivity of the Diamond/Cu-Ti composites.