摘要
采用电镀CBN砂轮,以镍基合金GH4169为工件材料,实验研究了两种离子液体的微量润滑磨削加工性能,分别是1-丁基-3-甲基咪唑四氟硼酸盐([BMIM]BF_(4))和1-己基-3-甲基咪唑四氟硼酸盐([HMIM]BF_(4)),并采用分子动力学模拟,揭示了离子液体在磨粒/工件界面物理吸附膜的形成机制,进一步开展了工件已加工表面的X射线光电子能谱(XPS)分析,揭示了离子液体在磨粒/工件界面化学反应膜的形成机制。研究结果表明:上述两种离子液体适合作为磨削液应用于微量润滑磨削加工中,既能较干磨大幅降低磨削比能和磨削力比,提高工件已加工表面质量,又能较干磨大幅降低磨削温度达100℃以上,避免磨削烧伤;磨粒磨钝表面由于微破碎所形成的凹槽状断口是离子液体进入磨粒/工件界面的输运通道,离子液体分子通过吸附在凹槽状断口内形成边界润滑膜,通过减小磨粒工件之间的直接接触面积来减小摩擦力;在微量润滑磨削加工过程中,以上两种离子液体均与工件在磨削界面上发生化学反应,形成了氟化物与氧化物共存的化学反应膜。
The grinding properties of two kinds of ionic liquids serving as grinding fluids were investigated experimentally under MQL,which were 1-butyl-3-methylimidazolium tetrafluoroborate([BMIM]BF_(4))and 1-hexyl-3-methylimidazolium tetrafluoroborate([HMIM]BF_(4)),respectively,with electroplated CBN grinding wheel and with nickel-based alloy GH4169 as workpiece material.And molecular dynamics simulations were adopted to reveal the formation mechanism of the physical adsorption film formed by the ionic liquids on the grain/workpiece interfaces.Further,X-ray photoelectron spectroscopy(XPS)analysis was carried out on the machined surfaces of the workpieces to reveal the formation mechanism of the chemical reaction film on the grain/workpiece interfaces.The results show that the two kinds of ionic liquids above are suitable for serving as grinding fluids under MQL.Compared with dry grinding,the ionic liquids may greatly reduce specific grinding energy and grinding force ratio,and improve the grinding quality of the machined surfaces of the workpiece,as well may greatly reduce grinding temperature up to more than 100℃,and avoid grinding burn.The fractured grooves on the grain wear flat areas due to micro-crushing are the transport channels for ionic liquids to enter into the grain/workpiece interfaces.The ionic liquid molecules may absorb in the fractured grooves to form boundary lubrication film,which may reduce the friction forces by decreasing the direct contact areas between the abrasive grains and the workpieces.During MQL grinding processes,the chemical reaction films consisting of fluoride and oxide are formed by the chemical reaction between the two kinds of ionic liquid and the workpieces on the grinding interfaces.
作者
王德祥
赵齐亮
张宇
高腾
江京亮
刘国梁
李长河
WANG Dexiang;ZHAO Qiliang;ZHANG Yu;GAO Teng;JIANG Jingliang;LIU Guoliang;LI Changhe(School of Mechanical and Automotive Engineering,Qingdao University of Technology,Qingdao,Shandong,266525;Key Lab of Industrial Fluid Energy Conservation and Pollution Control(Qingdao University ofTechnology),Ministry of Education,Qingdao,Shandong,266525)
出处
《中国机械工程》
EI
CAS
CSCD
北大核心
2022年第5期560-568,606,共10页
China Mechanical Engineering
基金
国家自然科学基金(51705272)
中国博士后科学基金(2018M642628)
青岛市应用基础研究计划(19-6-2-62-cg)。
关键词
磨削
微量润滑
离子液体
摩擦学机理
分子动力学
grinding
minimum quantity lubrication(MQL)
ionic liquid
tribological mechanism
molecular dynamics
