摘要
为了降低燃料电池空压机箔片气体轴承启停阶段的磨损,需在顶箔表面制备自润滑软涂层,但现有的聚四氟乙烯(PTFE)基或环氧树脂基软涂层仍存在摩擦系数较大或磨损率较高的问题。为此,在镍基高温合金箔片上制备聚酰亚胺(PI)基固体润滑涂层,研究涂层厚度、MoS_(2)纳米粒子掺杂含量和温度对涂层摩擦学性能的影响,并与商用PTFE涂层进行对比。结果表明,随着PI涂层厚度增加,其摩擦系数呈现先基本不变后增大的规律,且存在使摩擦系数最低的最佳涂层厚度。随着MoS_(2)纳米粒子掺杂含量增大,PI复合涂层摩擦系数和磨损率均呈现先减小后增大的规律,当掺杂含量为2.5%时,PI复合涂层摩擦系数低至0.173,磨损率低至9.14×10^(-6)mm^(3)/(Nm)。随着温度增加,PI复合涂层摩擦系数和磨损率呈现先减小后增大的规律,其摩擦系数在0.081~0.173范围,磨损率在3.77×10^(-6)~9.14×10^(-6)mm^(3)/(Nm)范围,相较于商用PTFE涂层,PI复合涂层摩擦系数最大降低幅度为43.4%,而磨损率更是降低了近两个数量级。
In order to decrease wear during the start-stop process of the foil gas bearing for the fuel cell air compressor,a self-lubricating soft coating is required on the surface of the top foil.However,the existing polytetrafluoroethylene(PTFE)-based or epoxy-based soft coating have problems such as high friction coefficient or poor wear resistance.Therefore,in this paper,polyimide(PI)-based solid lubricating coating is prepared on nickel-based superalloy foils.The effects of coating thickness,mass fraction of MoS_(2)nanoparticle and temperature on the tribological properties of the coating are studied and compared with commercial PTFE coating.The results show that with the thickness increasing,the friction coefficient of the prepared PI composite coating is basically unchanged at first and then increases,and there is an optimal coating thickness to minimize the friction coefficient.With the mass fraction of MoS_(2)nanoparticles increasing,the friction coefficient and wear rate of the PI composite coating first decrease and then increase.When the mass fraction is 2.5%,the friction coefficient of the PI composite coating is as low as 0.173,and the wear rate is as low as 9.14×10^(-6)mm^(3)/(Nm).With the temperature increasing,the friction coefficient and wear rate of the PI composite coating first decrease and then increase,and the friction coefficient is in the range of 0.081~0.173,while the wear rate is in the range of 3.77×10^(-6)~9.14×10^(-6)mm^(3)/(Nm).Compared with the commercial PTFE coating,the maximum reduction of friction coefficient of PI composite coating is 43.4%,while the wear rate decreases by nearly two orders of magnitude.
作者
张帅帅
王晓力
胡燕强
李志浩
王晨飞
ZHANG Shuaishuai;WANG Xiaoli;HU Yanqiang;LI Zhihao;WANG Chenfei(School of Mechanical Engineering,Beijing Institute of Technology,Beijing 100081,China)
出处
《功能材料》
CAS
CSCD
北大核心
2023年第3期3024-3028,3033,共6页
Journal of Functional Materials
基金
国家重点研发基金项目(2022YFB3402700)
中国博士后科学基金项目(2022M720432)
国家自然科学基金项目(51735001,11472046)。
