摘要
结合国内外对混合纳米流体微量润滑磨削的研究现状,研究二硫化钼和碳纳米管混合纳米流体微量润滑磨削镍基合金的工件表面质量。以工件表面粗糙度Ra值、表面轮廓曲线的自相关分析和工件表面微观形貌,作为表面质量表征参数。试验结果表明:纳米流体微量润滑由于纳米粒子高的强化换热能力从而避免了工件烧伤;混合纳米流体由于起到了'物理协同作用',较单一纳米流体得到了最低的表面粗糙度Ra值(0.311μm)和磨削温度峰值(52.8℃);随纳米流体质量分数的增加,表面粗糙度Ra值呈现上升趋势,这是由于质量分数的增加改变了微量润滑雾滴与工件的接触角,从而改变了浸润面积;而摩擦因数和磨削温度峰值在6%取得最低值后呈上升趋势,这是由于纳米粒子的团聚破坏了纳米流体性能。通过工件表面轮廓曲线的自相关分析进一步验证,纳米粒子在磨削区起到'润滑作用'和'微加工'作用,从而提高了加工精度。因此,综合磨削性能、表面粗糙度和自相关分析,选择混合纳米流体质量分数6%为纳米流体的优选质量分数。
An experimental research on effect of MoS2/CNTs hybrid nanofluid minimum quantity lubrication（MQL） grinding on workpiece surface quality of difficult-to-cut materials is carried out based on research status of nanofluids MQL. Surface roughness Ra, autocorrelation analysis of contour curve and surface topography（SEM） are studied in research. Experimental results show that nanofluid MQL avoid burn phenomenon due to nanoparticles can significantly improve heat transfer of nanofluids. The MoS2/CNT hybrid nanoparticles achieve lower surface roughness Ra value and grinding peak temperature than single nanoparticles because of "physical synergistic effect". Influenced by viscosity of nanofluids, surface roughness（Ra） increases gradually with the increase of mass fraction of nanofluid. Friction coefficient and grinding peak temperature, influenced by "agglomeration", decreases firstly and then increases with the increase of mass fraction of nanofluid, reaching the valley at 6%. According to the autocorrelation analysis, nanoparticle improves the grinding accuracy due to the "lubrication effect" and "micro-machining". It conclude that 6%, "agglomeration" phenomenon occurred concentration, MoS2/CNTs is the optimum concentration for nanofluid MQL in the experiment.
出处
《机械工程学报》
EI
CAS
CSCD
北大核心
2018年第1期161-170,共10页
Journal of Mechanical Engineering
基金
国家自然科学基金(51575290,51175276)
青岛市应用基础研究计划(14-2-4-18-jch)
黄岛区应用研究(2014-1-55)资助项目
关键词
磨削
微量润滑
混合纳米流体
表面质量
自相关分析
grinding
minimum quantity lubrication(MQL)
MoS2/CNTs nanofluids
workpiece surface quality
autocorrelation analysis
