(蘭州空間技術物理研究所 真空技術與物理重點實驗室，蘭州 730000)
摘 要: 采用真空氣體霧化法制備了TC4合金粉末，并采用激光粒度分析儀、掃描電子顯微鏡和霍爾流速計等對制備的粉末粒度分布、組織形貌、松裝密度、流動性等進行了測試分析。結果表明：真空氣體霧化法制備的TC4合金粉末粒度呈正態(tài)分布，尺寸集中分布在32.52~182.50 μm左右，粉末中值粒徑d50為92.70 μm，粉末球形度高，氧含量低(0.14%)；粉末具有較低的松裝密度和良好的流動性，粒徑在38~106 μm的粉末其流動性為25~50 s/(50 g)，松裝密度為2.52~2.56 g/cm3。TC4合金粉末中粒徑較大的顆粒表面呈發(fā)達的近似等軸的胞狀枝晶組織，而顆粒粒徑越小，其表面越光滑。少部分小顆粒粘附在大顆粒表面上，出現(xiàn)連體的“衛(wèi)星”狀。
關鍵字: 真空氣體霧化；TC4合金；球形粉末；微觀組織；霧化機理
（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
