使用200nm、1μm、2μm和10μm等粒度的高纯钨粉末，借助放电等离子烧结（SPS炉）进行快速的高温压力烧结，制备出尺寸为φ60 × 10mm的样品。烧结气氛为真空，烧结压力50MPa，烧结温度为1350-1500℃，保温时间为10分钟。借助阿基米德排水法测试样品的烧结密度，然后用烧结密度除以理论密度，获得烧结纯钨样品的相对密度值。使用Origin软件绘制出纯钨样品的相对密度变化曲线，反映初始粉末粒度和烧结条件对纯钨致密度的影响。取样进行标准金相样品的机械研磨和精密抛光，精密抛光使用0.5μm的金刚石研磨膏。借助扫描电镜观察金相样品内部的孔洞形貌和分布，反映致密度情况。另外，将金相样品折断，借助扫描电镜观察样品断口表面的孔洞分布和原始颗粒间的冶金结合质量。

High purity tungsten powders with particle sizes of 200nm, 1μm, 2μm and 10μm were sintered by spark plasma sintering (SPS furnace) at high temperature and pressure. The sintering atmosphere is vacuum, sintering pressure is 50MPa, sintering temperature is 1350-1500℃, holding time is 10 minutes. By means of Archimedes drainage method, the sintering density of the sample is measured, and then the sintering density is divided by the theoretical density to obtain the relative density of the sintered pure tungsten sample. Origin software was used to draw the relative density curve of pure tungsten samples, reflecting the influence of initial powder size and sintering conditions on the density of pure tungsten. Samples were taken for mechanical grinding and precision polishing of standard metallographic samples using 0.5μm diamond grinding paste. The pore morphology and distribution of metallographic samples were observed by scanning electron microscope to reflect the density. In addition, the metallographic samples were broken and the distribution of pores on the surface of the samples and the metallurgical bonding quality between the original particles were observed by scanning electron microscopy.