SUN Hang1，JIA Junhong1,2，YANG Jie1，HE Nairu1，YANG Xinran1，CAI Liangchen1
(1. School of Mechanical and Electrical Engineering, Shanxi University of Science and Technology, Xian 710021, China;2. Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000，China)
Abstract: MoO3-Bi2O3 (MB) nano-agglomerated composite powders for plasma spraying were prepared by high-energy ball milling and spray granulation combined with heat treatment. Using laser particle size analyzer, hall flowmeter, high-resolution field emission scanning electron microscope, X-ray diffractometer and other methods to investigate the effect of the mass fraction of MB powder in the ball mill slurry and the heat treatment temperature on the particle size distribution, density, sphericity, bulk density and fluidity of the composite powder. The friction performance of the coating made of the powder was tested at room temperature to 800 ℃. The results showed that MB nano-structure composite powders with particle size distribution ranging from 33.77 μm to 54.96 μm were obtained by mechanical ball milling and spray granulation. With the increase of the mass fraction of MB powder in the ball-milling slurry, the morphology of the powders obtained by spray granulation gradually tended to be regular spherical, and the particle size distribution first narrowed and then widened. It was found that the suitable mass fraction of MB powder in the ball-milling slurry was 35%, but the structure particles of the powders obtained were loose and not dense. The results show that the optimal heat treatment temperature of the composite powder is 500 ℃, when the loose density is 1.98 g/cm3, the flow time of 50 g powder is 25.97 s, the particle size distribution is 39.26～51.62 μm, and no new phase is generated by solid phase reaction. The coating is as low as 0.2 at 400 ℃, and the wear rate is as low as 9.28×10-5mm3/(N·m) at 600 ℃.
Keywords: high energy ball mill; spraying-dry; heat treatment; nanostructure; plasma spraying
中图分类号：TG174.44
文献标志码：A
文章编号：1008-5548(2021)06-0029-08
DOI:10.13732/j.issn.1008-5548.2021.06.004
收稿日期： 2021-04-01，修回日期：2021-05-26，在线出版时间：2021-10-18 14:26。
基金项目：国家自然科学基金项目，编号：51675508；陕西省重点研发计划项目，编号：2019GY-173。
第一作者简介：孙航(1997—)，男，硕士研究生，研究方向为高温润滑耐磨涂层。E-mail：787796716@qq.com。
通信作者简介：贾均红(1974—)，男，博士，教授，博士生导师，研究方向为摩擦学及表面技术。E-mail：jhjia@sust.edu.cn。
