Pan Yanpeng, He Xinbo, Ren Shubin, Wu Mao, Qu Xuanhui
Institute for Advanced Materials and Technology, University of Science and Technology Beijing, Beijing 100083, China.
Materials (Basel). 2019 Feb 4;12(3):475. doi: 10.3390/ma12030475.
In this study, diamond-copper composites were prepared with ZrC/Zr-coated diamond powders by spark plasma sintering. The magnetron sputtering technique was employed to coat the diamond particles with a zirconium layer. After heat treatment, most of the zirconium reacted with the surface of diamond and was transformed into zirconium carbide. The remaining zirconium on the zirconium carbide surface formed the outer layer. Owing to the method used to produce the ZrC/Zr-coated diamond in this study, the maximum thermal conductivity (TC) of 609 W·m·K was obtained for 60 vol. % diamond-copper composites and the corresponding coefficient of thermal expansion (CTE) reached as low as 6.75 × 10 K. The bending strength of 40 vol. % ZrC/Zr-coated diamond-copper composites reached 255.95 MPa. The thermal and mechanical properties of ZrC/Zr-coated diamond-copper composites were substantially superior to those of uncoated diamond particles. Excellent properties can be attributed to the strengthening of the interfacial combination and the decrease in the interfacial thermal resistance due to the improvement associated with the ZrC/Zr coating. Theoretical analysis was also proposed to compare the thermal conductivities and CTE of diamond-copper composites fabricated with these two kinds of diamond powders.
在本研究中，采用放电等离子烧结法，用ZrC/Zr包覆的金刚石粉末制备了金刚石-铜复合材料。利用磁控溅射技术在金刚石颗粒表面包覆一层锆层。热处理后，大部分锆与金刚石表面反应并转化为碳化锆。碳化锆表面剩余的锆形成外层。由于本研究中用于制备ZrC/Zr包覆金刚石的方法，对于60体积%的金刚石-铜复合材料，获得了609W·m·K的最大热导率，相应的热膨胀系数低至6.75×10K。40体积%的ZrC/Zr包覆金刚石-铜复合材料的抗弯强度达到255.95MPa。ZrC/Zr包覆金刚石-铜复合材料的热性能和力学性能明显优于未包覆金刚石颗粒的复合材料。优异的性能可归因于ZrC/Zr涂层带来的界面结合增强和界面热阻降低。还进行了理论分析，以比较用这两种金刚石粉末制备的金刚石-铜复合材料的热导率和热膨胀系数。
