衬垫甘油醚改性处理对自润滑关节轴承性能的影响

由于芳纶材料的苯基团极难溶于大多数化学物质,由聚四氟乙烯(PTFE)纤维和芳纶纤维复合编织而成的自润滑衬垫与黏接剂的黏接性能较差,从而影响轴承的整体性能。对关节轴承自润滑衬垫进行甘油醚接枝改性处理,利用摩擦学动态性能试验机测定衬垫改性处理后的轴承的摩擦学性能,并分析衬垫改性处理影响轴承摩擦学性能的机制。结果表明:衬垫经改性处理后轴承的磨损量、摩擦因数和摩擦温升均明显降低;经接枝改性处理后,衬垫的成膜性能得到明显改善,且随着摆动频率的提高,衬垫的成膜性能也有所提高,表明甘油醚接枝改性改善了自润滑关节轴承的摩擦学性能。     

改性处理衬垫对自润滑关节轴承粘接性能及摩擦学性能的影响

通过对PTFE纤维与芳纶纤维复合编织衬垫分别进行丙烯酰胺处理、磷酸酯偶联剂处理和甘油醚处理,利用Instron5944型电子万能材料试验机和自制的复合摆动式摩擦磨损性能试验机,对关节轴承的剥离强度及摩擦磨损性能进行了测试和试验,考察了不同改性处理对自润滑关节轴承的粘接性能和摩擦学性能的影响,结果表明,衬垫经改性处理后轴承的粘接性能得到了提高,并且轴承的摩擦因数、磨损量以及摩擦温升有所降低,其中经丙烯酰胺处理后,轴承的粘接性能和摩擦学性能最优。     

PTFE/芳纶纤维编织衬垫自润滑关节轴承的黏接性能及摩擦学性能

对PTFE/Kevlar纤维混合编织衬垫分别进行超声波处理、稀土CeO2处理后,制备了自润滑关节轴承,利用Instron5944型电子万能材料试验机和自制的高频摆动摩擦磨损试验机对关节轴承进行了剥离强度测试和摩擦磨损性能试验,考察了前处理工艺对关节轴承的黏接性能和摩擦学性能的影响,并采用扫描电镜(SEM)观察分析了衬垫表面的微观形貌变化,以探究轴承的摩擦学性能与衬垫形成PTFE转移膜的成膜性能之间的关系。结果表明,衬垫经改性前处理后,不仅提高了衬垫与基体的黏接性能,而且提高了轴承的摩擦学性能;轴承的摩擦学性能与其在摩擦磨损过程中形成PTFE转移膜的成膜性能之间存在一定的对应关系,即PTFE转移膜的形成越快,耐磨性、均匀连续性越好,在摩擦磨损过程中表现出较优的摩擦诱导成膜性能,其摩擦学性能也越优。     

PTFE/铜网衬垫关节轴承的摩擦学性能研究

利用自制的高频重载关节轴承摩擦磨损试验机,研究了不同摆动频率和接触压力条件下PTFE/铜网复合材料衬垫关节轴承摩擦系数、线磨损量和摩擦温度的变化规律。借助扫描电子显微镜(SEM)和能谱分析仪(EDS)分析了关节轴承衬垫的磨损表面并探讨了其磨损机理。结果表明:在接触压力≤47.6 MPa时,摆动频率的升高对轴承的摩擦系数、磨损量和摩擦温度影响较小;在接触压力(47.6 MPa时,随着摆动频率的变化,轴承的摩擦系数、磨损量波动范围较大,摩擦温度上升较快;在摆动频率和接触压力共同作用下衬垫材料发生塑性变形、挤压变形和剥落,内圈材料向衬垫转移使关节轴承衬垫自润滑能力下降,导致衬垫材料发生粘着磨损和磨粒磨损而失效。     

不同黏结方向对织物自润滑衬垫磨损性能的影响

织物自润滑衬垫是飞机关节轴承的关键自润滑材料,其摩擦磨损性能直接影响关节轴承的服役可靠性。对2种型号的关节轴承进行故障分析,结合摆动磨损试验研究衬垫裁剪和黏结方向对衬垫性能的影响。结果表明:45°方向裁剪的衬垫摩擦平稳性和耐磨性均优于0°方向裁剪的衬垫,为提高国产织物自润滑衬垫的服役性能提供了试验依据。     

编织衬垫自润滑关节轴承摩擦磨损性能的模糊综合评价与优化

综合应用正交试验与模糊综合评价方法,对影响自润滑关节轴承摩擦磨损性能各因素的主效应、两两因素之间的交互效应及全部因素水平搭配之间的交互效应进行综合分析,并依据分析结果确定最优参数组合,弥补方差分析只能研究单目标问题,不能全面反映实际情况的不足,为在不同工况条件下合理选择轴承类型提供依据。研究结果表明,各因素对编织衬垫自润滑关节轴承摩擦磨损性能的影响程度依次为:衬垫材料、摆动频率、前处理工艺;衬垫材料与摆动频率的交互效应对综合指标影响显著。     

PTFE/芳纶织物衬垫自润滑关节轴承性能试验

对比分析研究了同型号国产与进口PTFE/芳纶织物衬垫自润滑关节轴承的粘结质量、摩擦学性能以及承载性能,研究结果表明:进口轴承的剥离强度、摩擦磨损性能以及承载性能均略优于国产同型号的关节轴承;国内自润滑关节轴承的衬垫粘结质量、摩擦学性能以及承载性能需要进一步提高。     

关节轴承磨损性能试验研究进展

总结了关节轴承的磨损性能试验以及摩擦磨损试验机的研究进展。影响关节轴承摩擦磨损性能的主要因素为载荷、摆频、摆动角度、温度、轴承材料和自润滑材料材质及含量,并根据已有的研究工作对将来试验机的发展趋势提出了一些看法。     

PTFE/铜网复合材料衬垫自润滑关节轴承的试验研究

建立了自润滑关节轴承的摆动工况模拟试验方法和试验装置，试验评价了PTFE／铜网复合材料衬垫的关节轴承在不同载荷条件下无油润滑的摩擦磨损性能。结果表明：随着载荷自20kN增大至40kN，该轴承摩擦系数和线磨损量均有所增大，摩擦状态也发生了变化；40kN载荷已达到或超过该衬垫关节轴承的承载极限。     

铜基粉末冶金和青铜衬垫杆端关节轴承摩擦学性能对比

采用自制的高频重载杆端关节轴承摩擦磨损试验机,在摆动频率3 Hz,接触应力8 MPa条件下试验分析了铜基粉末冶金和青铜衬垫杆端关节轴承的摩擦因数、温升和磨损情况,借助扫描电子显微镜(SEM)检查分析了2种衬垫的表面磨损差异。结果表明:铜基粉末冶金衬垫轴承的摩擦学性能优于青铜衬垫,且前者为轻微磨粒磨损,后者为严重磨粒磨损。     

Influence of Ultrasonic Modified Liners on the Adhesive and Tribological Performances of Self-Lubricating Radial Spherical Plain Bearings

For self-lubricating spherical plain bearings, poor interface bonding strength between the polytetrafluoroethylene (PTFE)/aramid fabric hybrid woven liners and the outer rings can influence the full play of tribological performance of the self-lubricating liner. To solve this problem, the liners were modified by ultrasonic treatment. The adhesive performances of the modified and unmodified liners and the tribological performance of the self-lubricating radial spherical plain bearings with two kinds of liners were tested and compared. Results show that ultrasonic modification can improve the bonding performance of the liners significantly; compared to unmodified liners, the modified liners can decrease the friction coefficient, wear loss, and friction temperature of the bearings, which shows that ultrasonic modification can improve the tribological performance of self-lubricating spherical plain bearings. Bearings with modified liners only produced slight adhesive wear, but bearings with unmodified liners produced moderate adhesive wear and slight abrasive wear during test procedures.     

Investigation on MoS2 and graphite coatings and their effects on the tribological properties of the radial spherical plain bearings

With constant enlargement of the application areas of the spherical plain bearings, higher quality lubrication of the bearings is required. To solve the lubricating problems of spherical plain bearings under high temperature, high vacuum, high speed, heavy loads and strong oxidation conditions, it is urgent for us to develop more excellent self-lubricating technologies. In this paper, the bonded solid lubricant coatings, which use inorganic phosphate as the binder, the mixture of MoS2 and graphite with two different weight proportions as the solid lubricant, are prepared by spraying under three different spray gun pressures. The bonding strength tests on the coatings show that the best spraying pressure is 0.2 MPa and the better mixing proportion of MoS2 to Graphite is 3:1. Then for the radial spherical plain bearings with steel/steel friction pair, after the coatings are made on the inner ring outer surfaces, the friction coefficient, the wear loss and the friction temperature of the bearings under four oscillating frequencies are investigated by a self-made tribo-tester. The test results, SEM of the worn morphologies and EDS of worn areas show that tribological properties of the bearing are obviously improved by the bonded solid lubricant coatings. When sprayed under the spray gun pressure of 0.2 MPa, the bearings have better anti-friction and anti-wear properties than those sprayed under 0.1 MPa and 0.3 MPa. Further as proved from the XPS analysis, between the coating with 3:1 mixing ratio of MoS2 to Graphite and the coating with 1:1 ratio, the former has less oxidation occurred on the surface and therefore has better tribological characteristics than the latter. This paper provides a reference to developing a new product of the radial spherical plain bearings with high bonding strength, oxidation resistance and abrasion resistance.     

GF/PTFE自润滑纤维复合材料磨损性能热衰退研究

针对高频摆动关节轴承摩擦热对自润滑纤维复合材料摩擦磨损性能的影响,研制了高频使用条件下的玻璃纤维增强聚四氟乙烯(GF/PTFE)自润滑纤维复合材料,利用MYB～500高频高载摆动摩擦磨损试验机,对其进行不同摩擦温度下的摩擦磨损性能测试,研究摩擦热作用下材料自润滑性能和磨损性能衰退特征,分析磨损产物和摩擦表面以及不同摩擦温度下材料的磨损机理。结果表明,摩擦热对材料自润滑性能影响显著,适当的摩擦温度范围能够保证材料的自润滑性能,摩擦温度和摩擦因数之间互为耦合作用,对材料的磨损性能具有一定的影响;高摩擦热作用于自润滑过程及机理的改变,造成材料的磨损性能衰退现象。因此,不同温度下材料的磨损特征具有明显的差异化,其中低摩擦温度下(60～120℃)材料自润滑性能优异,磨损率很低;140℃摩擦温度条件下材料摩擦磨损性能开始衰退;材料在高摩擦温度下(140～180℃)的磨损初期自润滑性能良好、磨损轻微,而中后期磨损严重。微观分析表明,低摩擦温度下材料的磨损机理以轻微粘着和疲劳磨损为主;高摩擦温度下材料的磨损以片状剥落、纤维剪切破坏为主,且磨损面局部损伤特征明显,磨损严重。     

织物衬垫自润滑关节轴承的研究现状与展望

针对飞行器等高端设备中广泛使用的免维护织物衬垫自润滑关节轴承,从其基体与自润滑织物衬垫材料、力学仿真与结构分析、性能试验、磨损与寿命分析诸方面介绍了国内、外的研究动态和发展趋势,并在总结现有研究工作的基础上,对织物衬垫自润滑关节轴承的未来发展趋势提出了一些看法.     

Film-forming mechanisms for self-lubricating radial spherical plain bearings with hybrid PTFE/aramid fabric liners modified by ultrasonic

PTFE/aramid woven fabric liners were modified by ultrasonic. With self-made wear tester, tribological properties of the self-lubricating radial spherical plain bearings with modified and unmodified liners over swivel times were investigated. With scanning electron microscope and energy disperse spectroscopy, the film-forming mechanisms were analyzed. Results show: ultrasonic modification can improve tribological performances of the liners. Through ultrasonic modification, continuous and stable PTFE transfer films which had better wear resistance formed in a shorter time. Bearings with modified liners occurred slight adhesive wear, while the bearings with unmodified liners occurred serious adhesive wear and abrasive wear during the test process.     

Friction and wear properties of cu and fe-based P/M bearing materials

The performances of porous bearings under different operating conditions were experimentally investigated in this study. Material groups studied are 90%Cu+10%Sn bronze and 1%C + % balance Fe iron-based self-lubricating P/M bearings at constant (85%) density. In the experiments, the variation of the coefficient of friction and wear ratio of those two different group materials for different sliding speeds, loads, and temperatures were investigated. As a result, the variation of the friction coefficient - temperature for both constant load, and constant sliding speed, friction coefficient - average bearing pressure, PV - wear loss and temperature-wear loss curves were plotted and compared with each other for two materials, separately. The test results showed that Cu-based bearings have better friction and wear properties than Fe-based bearings.     

高频摆动自润滑关节轴承故障分析与改进验证

对高频摆动工况下自润滑关节轴承GE20-1的故障分析显示:织物自润滑衬垫和内圈球面镀硬铬涂层耐磨损性能不佳,出现偏磨现象;磨损严重处衬垫磨穿,内圈球面涂层仅剩1～2μm.为提升轴承耐磨损性能,采用了PTFE纤维面密度约20.1％的CD2#衬垫与内圈球面硬质合金涂层相组合的改进方案,改进轴承GE20-2经1500 h寿命...     

UHMWPE基水润滑轴承摩擦及润滑特性的试验研究

针对纤维填料改性UHMWPE水润滑轴承的摩擦磨损性能进行研究。在平面摩擦磨损试验机上对玻璃纤维及碳纤维填料对UHMWPE复合材料摩擦性能进行试验,并分析GF-CF-UHMWPE材料与Thordon SXL材料在干摩擦、水润滑工况下的摩擦因数及磨损量。最后,采用径向水润滑轴承试验台对比研究了GF-CF-UHMWPE轴承和Thordon SXL轴承在不同载荷下摩擦因数随转速的变化规律。结果表明:纤维填料能显著增强UHMWPE的减摩性和耐磨性,GF-CF-UHMWPE材料具有更好的耐温性能,线性热膨胀系数也显著减小;GF-CF-UHMWPE轴承具有相同载荷下启动转速低,启动摩擦因数小的特性。