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1.
通过电子探针和X射线光电子能谱分析,表明进口铸铝件表面的阳极氧化膜经过减摩封孔处理,其耐磨性明显优于未作减摩封孔处理的国产件膜层.为此,介绍了几种减摩封孔处理方法.  相似文献   
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张颖  赵梅君 《金属制品》1999,25(2):45-46
合成了5种润滑油添加剂,经抗磨性能测试,筛选出其中一种作为拉拔润滑油的添加剂,研制出润滑性能较好的拉丝润滑油,并在首钢拉丝厂作工业应用试验。试验结果表明,该润滑油润滑性能好,钢丝产品质量有较大提高。  相似文献   
4.
为了进一步弄清润滑油添加剂二戊基二硫代氨基甲酸锑(SbDTC)在金属表面的摩擦化学行为,在实验室合成了SbDTC,利用四球试验机研究了其极压和抗磨性能,采用X射线光电子能谱仪(XPS)、扫描电镜(SEM)对边界润滑状态下形成的磨斑及磨斑表面典型元素的组成、化学状态和含量进行了分析.结果表明,SbDTC具有较好的抗磨性能和承载能力,其主要原因可能是其在摩擦过程中与金属表面作用,生成了由Sb_2O_3,FeS,Fe_2O_3和含氮有机物组成的边界润滑膜,起到了缓冲载荷和抑制磨损的作用.  相似文献   
5.
Poly-dialkyl phosphonates were synthesized by reacting methyl linoleate with dimethyl, diethyl, and di-n-butyl phosphites in the presence of free radical initiator and positively identified and characterized using gas chromatography–mass spectrometry (GC-MS), nuclear magnetic resonance (NMR; 1H, 13C, 31P), and Fourier transform infrared (FTIR). Neat poly-dialkyl phosphonates and their blends in high-oleic sunflower oil (HOSuO) and polyalphaolefin (PAO-6) base oils were investigated for their physical, chemical, and tribological properties. At room temperature, the poly-dialkyl phosphonates displayed much better solubility in HOSuO than in PAO-6. Solubility in the base oils increased in the order dimethyl?<?diethyl?<?di-n-butyl. Relative to methyl linoleate, the neat poly-dialkyl phosphonates displayed higher density, higher kinematic viscosity, higher oxidation stability, and better cold flow (lower pour point and cloud point) properties. As an additive (0–10% w/w) in HOSuO, increasing concentration of poly-di-n-butyl phosphonate resulted in increasing onset and peak oxidation temperatures and decreasing cloud point. Poly-di-n-butyl phosphonate blends in HOSuO also showed lower four-ball antiwear (AW) coefficient of friction (COF) and wear scar diameter (WSD) than corresponding blends with zinc dialkyl dithiophosphate (ZDDP). As an additive (0–10% w/w) in PAO-6 base oil, poly-di-n-butyl phosphonate displayed lower four-ball antiwear COF and comparable WSD relative to similar blends of ZDDP in PAO-6. The results indicate that poly-dialkyl phosphonates are promising biobased AW additives with comparable or better performance than current petroleum-based commercial AW additives such as ZDDP.  相似文献   
6.
利用含有防腐剂的润滑油和轴承珠进行模拟吸附实验,通过紫外光谱的测量方法对吸附实验前后的润滑油进行吸光度测量,发现了吸附实验前后润滑油紫外吸光度的区别, 利用郎伯-贝尔原理对润滑油与轴承珠接触界面膜中的吸附量进行了计算,证实了防腐剂在摩擦副表面的吸附作用;对含有抗磨剂和防腐剂的润滑油进行吸附实验,并测量了实验前后润滑油的紫外吸光度,发现了相同防腐剂质量分数、不同抗磨剂质量分数润滑油紫外吸光度有较大区别;通过紫外光谱测量和界面膜中防腐剂吸附量的计算方法,表征了抗磨剂对防腐剂在摩擦副表面吸附量的定性影响规律 ,证实了抗磨剂与防腐剂的竞争吸附关系。  相似文献   
7.
用四球摩擦磨损试验机考察了油溶性二烷基二硫代磷酸铜(CuDDP)和有机硼酸酯(OB)的减摩抗磨性能,探讨了CuDDP与OB的协同减摩抗磨作用的协同减摩抗磨作用;采用扫描电镜分析了磨斑表面化学状态和深度分布。结果表明,CuDDP和OB具有优良的减摩抗磨性能,且二者具有优异的协同减摩抗磨作用。其主要原因在于有机硼酸酯促进了二烷基二硫代磷酸铜的分解,形成了铜与硼的渗透层。  相似文献   
8.
Tests were performed on two different four‐ball testers. The first was used to determine antiwear (AW) and extreme pressure (EP) properties at sliding friction. The second was used to assess the surface fatigue (pitting) life at rolling movement. Lubricating oils of various chemical compositions were tested. A base mineral oil was blended with two different commercial packages of lubricating additives of AW and EP types. The AW additives contained ZDDP and were blended with the base oil at 0.2 and 3wt %. The EP additives were organic compounds of sulphur and phosphorus, blended with the base oil at 1 and 10wt %. It is shown that AW additives not only improve AW and EP properties but also — at 0.2% — are beneficial for the fatigue life. An increase in the concentration of AW additives leads to an improvement of AW and EP properties but — for one of the packages — reduces the fatigue life. EP additives — at 1% concentration — significantly improve EP properties, and to a lesser extent AW properties. Such a concentration of EP additives has no influence on the fatigue life. An increase in the concentration of EP additives leads to a further improvement of EP and AW properties. However, this is accompanied by a considerable decrease in the fatigue life. By using a scanning electron microscope and energy dispersive spectrometer for analysis of the worn surface, mechanisms of action of various lubricating additives under different friction conditions were identified. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
9.
Experimental techniques have been developed to measure the friction, antiwear film‐forming and wear properties of lubricants in rolling–sliding contact. Friction measurements show that zinc dialkyldithiophosphates (ZDDPs) and also some other phosphorus‐based additives increase friction in mixed lubrication. Film thickness measurements show that this increase in friction correlates with the thickness of antiwear film. They also reveal some of the drivers of antiwear film formation and removal. A novel wear tester is described which enables the mild wear resulting from ZDDP‐containing oils to be monitored. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
10.
硼酸盐润滑油添加剂的发展动态   总被引:13,自引:2,他引:11  
简要地阐述了硼酸盐润滑油加剂的发展现状和研究动态,对其多种制备方法进行了比较和总结,并重点对其性能和作用机理的研究进行了分析和归纳,特别强调指出,改善硼酸盐润滑油添加剂的储存稳定性和抗乳化性,研究其与含磷,硫,氮等活性元素添加剂的复配规律以及复配作用机理,是这一领域的主要趋势之一。  相似文献   
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