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用高能球磨法制取纳米晶W粉，在真空炉内将此W粉分别进行无压和热压烧结成致密块体。利用扫描电镜、透射电镜、X－ray衍射仪等观测球磨过程中粉末粒度、形貌和结构的变化以及烧结块体的质量密度随温度的变化，并与普通粉的烧结性能作了比较。结果表明：脆性材料在高能球磨过程中不出现片层状结构，一直保持颗粒状结构；纳米晶超细W粉与普通W粉相比，由于颗粒和晶粒小、扩散系数高、表面能高、比表面原子数多、晶格畸变严重、熔点低等使得烧结驱动力提高，物质迁移速率加快，其烧结性能大幅度提高。
Preparation of nanocrystalline W powder with high-energy ball milling method, the W powder in a vacuum furnace were pressureless and hot-pressed to compact block. The changes of particle size, morphology and structure during milling were observed by scanning electron microscopy, transmission electron microscopy and X-ray diffractometry. The mass density of the agglomerates varied with the temperature and compared with that of common powders. The results show that the brittle material does not appear lamellar structure during high-energy ball milling, and keeps the granular structure all the time. Compared with ordinary W powder, the ultrafine nanocrystalline W powder has higher diffusion coefficient and higher surface energy , More than the surface atomic number, serious lattice distortion, low melting point makes the driving force of sintering increased, the material migration rate accelerated, the sintering performance increased significantly.