Evaluation of Tribological Properties of Sulfur- and Phosphorous-Free Quinolinium Salts and Their Correlation with Quantum Chemical Parameters

For developing antiwear additives with high efficiency but with low sulfated ash, phosphorous, and sulfur (SAPS), N-substituted quinolinium halides, [DIP-Q]⁺Br^? [DIP-Q=1-(3-(1,3-dioxoisoindolin-2-yl)propyl)quinolon-1-ium], [DIE-Q]⁺Br^? [DIE-Q=1-(3-(1,3-dioxoisoindolin-2-yl)ethyl)quinolon-1-ium], [P-Q]⁺I^? [P-Q=propylquinolon-1-ium], and [M-Q]⁺I^? [M-Q=methylquinolon-1-ium] have been prepared and characterized by ¹H- and ¹³C-NMR spectroscopic techniques. The tribological performance of these quinolone-based quaternary salts as antiwear additives in paraffin oil has been assessed on a four-ball test rig. The observed results have been compared with those of zinc dialkyldithiophosphate (ZDDP), a high SAPS additive. The tribotesting of these additives has been performed using 1% w/v additives concentration at different loads and times. The potential of these compounds as antiwear additives is evident from their observed tribological data: mean wear scar diameter (MWD), friction coefficient (µ), mean wear volume (MWV), and wear rates. All of the quinolinium derivatives prove to be better antiwear additives than ZDDP. Among the tested synthesized compounds, [DIP-Q]⁺Br^? exhibits the best tribological behavior followed by [DIE-Q]⁺Br^?, [P-Q]⁺I^?, and [M-Q]⁺I^?. The surface topography of worn surface studied by scanning electron microscopy (SEM) and atomic force microscopy (AFM) shows that surface roughness is reduced to a greater extent in case of quinolinium derivatives than lubrication with ZDDP or base oil alone. Energy-dispersive X-ray (EDX) and X-ray photoelectron spectroscopy (XPS) analysis of worn surfaces in the presence of quinolinium additives shows that the tribofilm is composed of FeBr₃, Fe₃O₄, and organic compounds containing carbonyl and imine bonds. Theoretical investigations using quantum chemical calculations are indicative of significant chemical interactions of these quinolinium additives with metal surfaces, which is strongly supported by the observed experimental data.     

亚磷酸双十二烷基酯的合成与摩擦性能研究

以亚磷酸二正丁酯和十二醇为原料,通过酯交换法合成亚磷酸双十二烷基酯。采用FTIR对其结构进行表征;以亚磷酸双十二烷基酯为极压抗磨剂,制备一种以多元醇酯为主油性剂的水基钢丝拉拔润滑剂,采用四球机和扫描电镜考察其摩擦性能。结果表明,合成的亚磷酸双十二烷基酯具有良好的极压抗磨性能,质量分数3.0%左右的亚磷酸双十二烷基酯,可使水基复合润滑液的最大无卡咬负荷提高75%,磨斑直径减小33.4%,摩擦因数降低31.6%,且磨痕表面相对光滑、磨痕分布均匀。     

润滑介质对摩擦性能影响差异分析

L-CKD150润滑油和复合锂基润滑脂广泛运用于石油装备润滑减磨。为研究2种润滑介质对摩擦副摩擦磨损性能及磨损机制的影响差异,采用MMW-1型微机控制立式万能摩擦磨损试验机,开展不同接触压力和线速度及不同润滑环境下摩擦学实验研究。结果表明:实验工况下,销-盘摩擦副表面以磨粒磨损为主,同时存在黏着磨损;相比于L-CKD150润滑工况,复合锂基润滑脂润滑时销-盘表面黏着磨损更为严重,进而加大摩擦因数的波动幅度,最大波动幅度为L-CKD150润滑下的3.7倍;盘试样表面磨粒磨损与接触压力有关,0.5 MPa接触压力下,L-CKD150润滑时磨粒磨损较严重,1.5 MPa下则复合锂基润滑脂润滑时更严重,磨粒磨损是影响盘试样磨损量差异的主要因素。     

固体润滑剂对丁腈橡胶复合材料性能的影响

将石墨、石墨烯以及两种不同尺寸的二硫化钼分别引入丁腈橡胶复合材料,考察四种固体润滑剂对复合材料性能,尤其是摩擦学性能的影响。结果表明,石墨烯的引入使丁腈橡胶复合材料的硬度及模量明显上升,扯断伸长率下降;而二硫化钼的引入有利于提高材料的撕裂性能。在干摩擦条件下,石墨烯的引入可有效提高材料的耐磨性并降低材料的摩擦系数,这得益于石墨烯对复合材料的润滑作用和硬度提高作用。此外,引入石墨和较大尺寸的二硫化钼亦可改善材料的耐磨性。在水润滑条件下,二硫化钼对降低摩擦系数的作用最好,石墨烯最有利于提高材料的耐磨性。     

羧甲基纤维素钠包覆二硫化钨固体润滑涂层的磨痕形貌与热重性能

为了改善WS_2在涂料中的分散性能,将WS_2颗粒用羧甲基纤维素钠包覆并制成涂料,气压喷涂在基体表面形成固体润滑涂层。分别采用场发射扫描电子显微镜、金相显微镜和数码显微镜对固体润滑涂层及其颗粒进行了表征;在MMW-10销-盘磨损试验机上评价了固体润滑涂层在载荷128 N,转速180 r/min,600 s条件下的摩擦磨损性能。结果表明:包覆的WS_2悬浮稳定性显著提高;固体润滑涂层的磨损量及平均摩擦系数均显著降低,磨损量由77 mg降至4 mg,摩擦系数由0.180降低至0.083,且磨痕形貌比较光滑;固体润滑涂层表现出较好的润滑性能。     

纳米MoS2的制备及其在润滑油添加剂中的研究现状

纳米二硫化钼(MoS₂)是典型的类石墨烯二维材料,具有出色的电学、光学、热学和力学性能,是当前研究的热点之一。本综述详细介绍了二维碳纳米材料-二硫化钼的纳米摩擦学性能,以及作为润滑油添加剂的研究进展,总结了二硫化钼的各种纳米摩擦机理,阐述了通过机械剥离法、锂离子插层法、水热法等制备纳米二硫化钼的方法;总结了纳米MoS₂在润滑领域的应用,阐述了利用表面修饰以及制备复合材料的方法可提高二硫化钼在润滑油中的分散稳定性;并指出了纳米MoS₂作为高性能润滑材料仍需解决的问题及未来的研究趋势。     

铈掺杂白云母复合粉体的制备及其减摩抗磨机理

采用机械力固相化学反应法制备了稀土铈掺杂白云母(Muscovite,MC)的复合粉体(Ce-MC),表征了粉体的微观形貌、晶体结构、元素组成和粒径分布。利用四球摩擦磨损试验机考察比较了MC和Ce-MC作为润滑脂添加剂的摩擦学性能,对磨损表面进行了SEM、EDS和XPS分析,并探讨了Ce-MC的减摩抗磨机理。结果表明:CeMC复合粉体中铈化合物包覆在白云母粉体表面,主要物相为CeO_2;Ce-MC和MC作为添加剂均能提高锂基润滑脂的减摩抗磨性能,且Ce-MC复合粉体的摩擦学性能优于MC单体;Ce-MC优良的摩擦学性能与其磨损表面Ce-MC的物理吸附膜和主要成分为Fe_2O_3、SiO_2的化学反应膜有关。     

盒形件成形工艺分析

目的分析盒形件的成形规律,解决盒形件的成形问题。方法对毛坯展开料、拉伸次数、压边圈的选用、模具等几个主要参数及拉伸零件所需的冲床规格进行计算,制订加工工艺方案。分析零件在拉伸过程中有可能出现的皱痕、划痕、拉断等问题,从而采取合适的润滑剂。结果以典型盒形件为例,进行试加工,零件尺寸100%合格,零件表面质量良好。结论通过工艺参数计算原则及润滑剂的选用,能够保证盒形件的尺寸精度、表面质量,提高生产效率。该方法对类似零件的工艺计算和分析有一定的参考价值。     

新型防锈润滑添加剂的合成研究

以柠檬酸、壬基酚聚氧乙烯醚和二乙醇胺为原料合成了一种具有防锈、润滑双重功能的水基合成切削液添加剂———柠檬酸壬基酚聚氧乙烯醚单酯二乙醇酰胺。柠檬酸酐的制备条件为柠檬酸∶乙酸酐(摩尔比)为1.0∶1.2,温度为35℃,反应时间为18h;酯化摩尔比(酸酐∶OP)为1.0∶1.2,温度为80~90℃,反应时间为3h;酰胺化条件为柠檬酸壬基酚聚氧乙烯醚单酯∶二乙醇胺(摩尔比)为1∶1.5,反应温度为130~140℃,反应时间为3~4h。采用红外光谱法对产物进行表征,进而确定了合成的最佳工艺路线和工艺条件。     

Factice from oil mixtures

High-quality brown factice is produced from meadowfoam and rapeseed oils, while a poorer-quality factice is produced from soybean oil, a less expensive oil. A one-to-one mixture of soybean and meadowfoam or rapeseed oil produces a factice that has similar physical characteristics as factice produced from 100% meadowfoam or rapeseed oils. In addition, meadowfoam oil and rapeseed oil act as accelerators when mixed with castor or jojoba oils. White factice productions from soybean oil can also be improved when mixed with meadowfoam or rapeseed oils. The difference in cost, obtained by using as much as 50% soybean oil instead of the higher-costing oil, will translate into significant savings for the factice and rubber industries.