Abstract Despite the great potential value as heat sink materials, their practical application of high thermal conductivity (TC) Cu-diamond composites is limited since high temperature and high pressure (above 1000 K and 60 MPa) were requisite in the conventional process. In this study, high TC void-free Cu-diamond composites reinforced with various diamond particles were prepared via composite electroplating. The impacts of diamond particle sizes (ranged from 10 to 400 μm) on microstructure, interface and TC of the composites were investigated. The TC of Cu-diamond composites was improved with the increase of diamond particle sizes and well-combined interface. Interestingly, a critical size for improved the TC of Cu-diamond composites was clearly observed and the critical value (22 μm) was derived from Kipitza theory. Based on the TC results and critical analysis, the Cu-diamond composite reinforced with large diamond particles (400 μm) was synthesized, which possessed the TC of 846.52 W m−1 K−1 and the thermal expansion coefficient of 7.2 × 10−6 K−1. Such attractive thermal properties suggested that electroplating Cu-diamond composites showed the promising application as heat sink materials in microelectronic industry.

中文翻译：

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复合电镀制备的各种金刚石增强Cu-金刚石复合材料的临界效应及增强热导率

摘要 尽管作为散热材料具有巨大的潜在价值，但由于传统工艺需要高温和高压（1000 K以上和60 MPa以上），因此其在高热导率（TC）铜-金刚石复合材料的实际应用受到限制。在这项研究中，通过复合电镀制备了用各种金刚石颗粒增强的高 TC 无空隙铜-金刚石复合材料。研究了金刚石粒径（10 至 400 μm）对复合材料微观结构、界面和 TC 的影响。Cu-金刚石复合材料的TC随着金刚石粒径的增加和结合良好的界面而提高。有趣的是，可以清楚地观察到提高铜-金刚石复合材料 TC 的临界尺寸，临界值 (22 μm) 来自 Kipitza 理论。基于TC结果和临界分析，合成了大金刚石颗粒（400 μm）增强的Cu-金刚石复合材料，其TC为846.52 W m-1 K-1，热膨胀系数为7.2 × 10-6 K-1。如此吸引人的热性能表明电镀铜-金刚石复合材料在微电子工业中作为散热材料显示出有前景的应用。