(兰州空间技术物理研究所 真空技术与物理重点实验室，兰州 730000)
摘 要: 采用真空气体雾化法制备了TC4合金粉末，并采用激光粒度分析仪、扫描电子显微镜和霍尔流速计等对制备的粉末粒度分布、组织形貌、松装密度、流动性等进行了测试分析。结果表明：真空气体雾化法制备的TC4合金粉末粒度呈正态分布，尺寸集中分布在32.52~182.50 μm左右，粉末中值粒径d50为92.70 μm，粉末球形度高，氧含量低(0.14%)；粉末具有较低的松装密度和良好的流动性，粒径在38~106 μm的粉末其流动性为25~50 s/(50 g)，松装密度为2.52~2.56 g/cm3。TC4合金粉末中粒径较大的颗粒表面呈发达的近似等轴的胞状枝晶组织，而颗粒粒径越小，其表面越光滑。少部分小颗粒粘附在大颗粒表面上，出现连体的“卫星”状。
关键字: 真空气体雾化；TC4合金；球形粉末；微观组织；雾化机理
（Science and Technology on Vacuum Technology and Physics Laboratory, Lanzhou Institute of Space Technology Physics, Lanzhou 730000, China）
Abstract:Spherical TC4 alloy powder was prepared by vacuum gas atomization. The particle size distribution was analyzed by laser particle size distribution analyzer. The morphology and microstructure were analyzed by scanning electron microscopy. The flowability and apparent density of the powder were analyzed by Hall funnel. The results show that the TC4 powder exhibits normal particle size distribution. The particle size of TC4 alloy spherical powder is in the range from 32.52 μm to 182.50 μm, and the median diameter of the powder is 92.7 μm. The powder has good sphericity and low oxygen content (0.14%, mass fraction). The powder with 38-106 μm in diameter has a low apparent density and a good fluidity, showing a flow time of 25-50 s/(50 g) and a apparent density of 2.52-2.56 g/cm3. In addition, the surfaces of coarse particles exhibit the equiaxial cellular dendritic structure. However, the smooth surfaces and structure refinement appear on the fine powder. Some fine particles adhere on the coarse particles surface, and exhibit the connection “satellite”.
Key words: vacuum gas atomization; TC4 alloy; spherical powder; microstructure; atomization mechanism
