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。
Pure tungsten, oxide dispersion strengthened tungsten and carbide dispersion strengthened tungsten were fabricated by high-energy ball milling and spark plasma sintering process. In order to evaluate the properties of the tungsten alloys under transient high heat flues, four tungsten samples with different grain sizes were tested by high-intensity pulsed ion beam with a heat flux as high as 160 MW/（m^2·s^-1/2）. Compared with the commercial tungsten, the surface modification of the oxide dispersion strengthened tungsten by high-intensity pulsed ion beam is completely different. The oxide dispersion strengthened tungsten shows inferior thermal shock response due to the low melting point second phase of Ti and Y2O3, which results in the surface melting, boiling bubbles and cracking. While the carbide dispersion strengthened tungsten shows better thermal shock response than the commercial tungsten.
