摘要：针对3D打印用钛合金粉 (Ti-6Al-4V) 分级工艺要求, 采用LNIST-180A-2型闭式氩气保护分级系统对其进行分级, 借助激光粒径分析仪、粉体流变仪、氧氮分析仪表征粉体粒径、流动性以及氧氮含量。结果表明:使用新型分级系统可以有效将钛合金粉分级为目标粒径段产品 (旋风分离器:0²0μm, 半涡分级机:20⁵0μm) , 在一级分级机和二级分级机转速分别为1 500、1 620 r/min, 系统压力控制在0¹.2 k Pa时, 钛合金粉的产量为8.24 kg/h;分级后的钛合金粉通气率由4.3提高至72.6, 流动性能大幅改善;分级后钛合金粉氧、氮含量均符合国家标准。该系统可以满足3D打印用钛合金粉的工业分级要求。

关键词：钛合金粉；3D 打印；闭式循环氩气保护分级系统

Abstract：Based on the classifying process requirements of titanium alloy powder (Ti-6Al-4V) used for 3D printing, the LNIST-180 A-2 closed argongas protection classification system was used to classify the powder. Particle size, morphology, fluidity and oxygen and nitrogen contents of the powder were indicated by laser particle size analyzer, powder rheometer, and oxygen nitrogen analyzer. The experimental results show that the titanium alloy powder can be effectively classified into the target particle size (cyclone separator: 0 ~ 20 μm, half vortex classifier:20 ~ 50 μm) using the new classification system. When the speed of the first grade classifier and the second grader are 1 500 r/min and 1 620 r/min respectively, and the system pressure is controlled at 0¹.2 k Pa, the output of titanium alloy powder is 8.24 kg/h.Meanwhlie, the aeration rate of the graded titanium alloy powder increases from 4.3 to 72.6, and the liquidity performance is greatly improved. Moreover, the contents of oxygen and nitrogen of titanium alloy are all up to the national standard after classification. After testing, the system can meet the industrial grading requirements for titanium alloy powder in 3D printing.

Keywords：titanium alloy；3D printing；closed-loop argon protection grading system