以钨粉和镀钛金刚石颗粒为原料，采用超高压力下通电烧结(resistance sintering under ultra high pressure， RSUHP)的方法制备钨−金刚石复合材料，利用X射线衍射(XRD)以及扫描电镜(SEM)对该复合材料的物相组成及断口形貌进行表征，利用LFA427激光热导测试仪测试材料的常温和高温热导率，并与纯钨的常温热导率进行对比，同时还分析在不同功率下烧结及不同温度下退火时，钨和金刚石的反应情况。结果表明，超高压烧结功率低于4.5 kW时，可避免碳化钨的生成；钨−金刚石复合材料作为高热导材料的适宜服役温度应低于900℃。金刚石的加入使钨的室温热导率从127.3 W/(m∙K)显著提高到176.3 W/(m∙K)，但随温度升高而降低。%Tungsten-diamond composites were prepared by resistance sintering under ultra high pressure (RSUHP) using tungsten powders and titanium plated diamond particles as raw materials. The phase composition and fracture morphologies were characterized by XRD and SEM. The thermal conductivity of pure tungsten at room temperature and tungsten-diamond composites at room temperature and elevated temperature were tested and compared using LFA427 laser thermal conductivity testing instrument. The tungsten-diamond reaction conditions of samples sintered by different power and annealed at different temperatures were investigated. The results show that WC can not form when the sintering power is lower than 4.5 kW. It can be determined that the appropriate working temperature of tungsten-diamond composite as high thermal conductivity material must be lower than 900 ℃. The addition of diamond makes the room temperature thermal conductivity improves from 127.3 W/(m∙K) to 176.3 W/(m∙K), which drops while temperature gets higher.
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