不同润滑条件对纳米Al2O3改性UHMWPE摩擦磨损性能的影响

用MPV 2 0 0型摩擦磨损试验机对纳米Al2 O3改性超高分子量聚乙烯 (UHMWPE)塑料合金材料在不同润滑条件下 (干摩擦、水润滑 )进行了摩擦学性能测定 ,分别考察了载荷、速度以及运行时间等对材料摩擦学性能的影响。为纳米Al2 O3改性超高分子量聚乙烯塑料的实际应用提供理论指导     

不同润滑条件对塑料合金轴承摩擦磨损性能的影响

用MPV 2 0 0型摩擦磨损试验机对超高分子量聚乙烯 (UHMW PE)塑料合金轴承在水润滑介质不同含沙量的条件下进行了摩擦学性能测定 ,分别考察了载荷、速度以及运行时间等对合金轴承摩擦学性能的影响。为水润滑合金轴承的实际应用提供理论指导。     

水润滑塑料轴承的摩擦性能研究

用MPV—200型摩擦磨损试验机测定了超高分子量聚乙烯(简称UHMW—PE)塑料合金轴承水润滑条件下的摩擦学性能，考察了载荷、速度、运行时间等因素对轴承摩擦系数和磨损率的影响，得出了摩擦学性能随各种因素的变化规律。并对作用机理进行了系统的分析，为水润滑超高分子量聚乙烯塑料合金轴承的实际应用提供理论依据。     

混杂纤维增强材料在水润滑条件下的摩擦学性能研究

以丁腈橡胶改性酚醛树脂为基体,芳纶/玻纤混杂纤维为增强纤维,经热压烧结制备一种矿井提升系统的摩擦材料,在水润滑条件下研究其摩擦学性能,并用扫描电镜(SEM) 观察材料的磨损形貌。结果表明,添加混杂纤维的摩擦材料相比未添加混杂纤维的摩擦材料具有更好的摩擦学性能,表现为低的摩擦因数和磨损率以及稳定的摩擦学性能。摩擦过程中,添加混杂纤维的材料的磨损机制为疲劳和塑性变形,未添加混杂纤维的材料的磨损机制主要表现为疲劳、犁沟以及少量黏着磨损。     

混杂纤维增强摩擦材料在水润滑条件下的摩擦学性能

以丁腈橡胶改性酚醛树脂为基体,芳纶/玻纤混杂纤维为增强纤维,经热压烧结制备一种矿井提升系统的摩擦材料,在水润滑条件下研究其摩擦学性能,并用扫描电镜(SEM)观察材料的磨损形貌。结果表明,添加混杂纤维的摩擦材料相比未添加混杂纤维的摩擦材料具有更好的摩擦学性能,表现为低的摩擦因数和磨损率以及稳定的摩擦学性能。摩擦过程中,添加混杂纤维的材料的磨损机制为疲劳和塑性变形,未添加混杂纤维的材料的磨损机制主要表现为疲劳、犁沟以及少量黏着磨损。     

摩擦学研究及发展趋势

简要评述了摩擦学研究的进展.指出极端条件下的摩擦、磨损与润滑性能,分子水平上的摩擦磨损本质,环境友好润滑材料,摩擦学失效问题及摩擦学设计是摩擦学研究的主要方向.     

超声振动对不同黏度润滑油摩擦学性能的影响

研究GCr15/45#钢摩擦副在4种不同黏度的润滑油润滑时,有和无超声振动下的摩擦磨损性能,采用扫描电子显微镜分析磨痕表面形貌,探讨在不同黏度润滑油作用下,超声振动对润滑油摩擦学性能的影响机制。结果表明:超声振动对不同黏度润滑油摩擦学性能的影响是不同的;超声振动可以提高低黏度润滑油润滑的减摩抗磨性能,如在6#白油润滑时施加超声振动后,摩擦副间的摩擦因数和磨损体积分别减小了13.6%和17.5%;高黏度润滑油润滑时,超声振动会加剧摩擦副的摩擦磨损,如在150BS润滑时施加超声振动后,摩擦副间的摩擦因数和磨损体积分别增加了10.4%和50%。     

水润滑硅基非氧化陶瓷摩擦学性能及其表面改性研究进展

综述了水润滑条件下硅基非氧化物陶瓷(Si3N4和SiC)摩擦学性能的研究状况,包括水润滑条件下其摩擦磨损特性以及其表面改性技术对其摩擦学性能的影响.硅基非氧化物陶瓷在水中显示出较低的摩擦因数以及良好的抗磨损能力;表面改性技术能有效地改善硅基非氧化陶瓷的水润滑摩擦磨损性能,离子注入技术是表面改性技术的一个重要发展趋势.     

表面粗糙度对纳米润滑添加剂摩擦学性能影响的研究

摩擦学系统的复杂性及多变性增加了对材料在摩擦试验过程的预见性的难度，通过XP销盘摩擦磨损试验机分别考察了钢／钢摩擦副住不同润滑介质中不同的表面粗糙度对其摩擦系数和磨损量的影响。试验结果表明：表面粗糙度对摩擦副的摩擦学影响是复杂的，在特定的润滑条件下，不同的表面粗糙度表现出不同的摩擦学性能。     

PTFE基复合材料海水润滑下的摩擦学性能研究

研究碳纤维/聚四氟乙烯（CF/PTFE）、玻璃纤维/聚四氟乙烯（GF/PTFE）复合材料与氮化硅陶瓷配副在海水环境下的摩擦学性能与润滑机制,分析滑动速度对摩擦副海水润滑性能的影响规律。结果表明：在海水润滑条件下,随着滑动速度的增加,PTFE、CF/PTFE、GF/PTFE材料与Si3N4陶瓷配副时的摩擦学性能均有明显改善,摩擦因数与磨损率均呈显著降低的趋势,其中CF/PTFE复合材料表现出更为优异的摩擦学性能,在1 000 r/min滑动速度下摩擦因数低至0.026。磨损表面表征结果表明,在海水润滑条件下,PTFE基复合材料在摩擦过程中由于摩擦化学反应生成了润滑膜,可为摩擦副提供良好的润滑和减磨作用,从而减少摩擦磨损行为的发生。     

多组分纤维混杂增强树脂基摩擦材料研究

为提高摩擦材料高温下的摩擦磨损性能和摩擦因数的稳定性,利用正交试验法对多种纤维增强酚醛树脂基摩擦材料的配方进行优化设计,并通过极差分析,探讨多种纤维及含量对摩擦材料性能的影响及摩擦材料的磨损机制.研究表明:混杂纤维增强树脂基摩擦材料有着优异的耐磨性.陶瓷纤维硬度较高,开散混料后能够均匀分布在树脂基体内,对酚醛树脂基摩擦...     

Tribological Characteristics of Binder Resins for Brake Friction Materials at Elevated Temperatures

The heat resistance of the multiphase friction materials made with straight phenolic resin (ST), boron–phosphorous (B–P)-modified phenolic resin (BP), or polyimide (PI) was investigated using a Krauss-type friction tester. Thermal analysis of the cured resins was also carried out to examine the chemical and mechanical properties of the resin and their effects on the wear rate and the coefficient of friction. The results showed that the fade and wear of the friction materials were closely related to the thermal decomposition of the binder resin and durability of the contact plateaus, which were produced by the compaction of wear debris around hard ingredients on the rubbing surface. The friction material containing the B–P modified resin was more resistant to wear and fade than the other binder resins. On the other hand, the friction material with polyimide showed good fade resistance but exhibited excessive wear despite its good thermal resistance.     

纤维增强树脂基摩阻材料的摩擦学研究进展

综述了纤维增强树脂基摩阻材料的研究和发展，主要分析了树脂基体、增强纤维和填料以及温度和PV值对摩阻材料摩擦学性能的影响及作用机理，简述了摩阻材料磨损机理的研究现状和主要磨损类型。并提出了今后研究摩阻材料应重视的问题。     

Effect of Aramid Pulp and Lapinas Fiber on the Friction and Wear Behavior of NBR Powder–Modified Phenolic Resin Composite

Short fiber reinforcement plays a definite role in governing the performance of a composite through the improvement of different material properties. The present investigation deals with the effect of aramid pulp and lapinas fiber on the friction and wear characteristics of a composite made from phenolic resin modified by powdered acrylonitrile butadiene rubber (NBR) on a pin-on-disc tribometer. Four composites, containing 10, 20, 30, and 40 wt% of aramid pulp with respect to phenolic resin content, were prepared. Another four composites, containing 50, 100, 200, and 300 wt% of lapinas fiber with respect to phenolic resin content, were also made. It was found that the two different fibers have distinctly different contributions to the friction and wear properties of the composites. It was also found that the incorporation of aramid pulp enhances friction stability of the composites much better than that of lapinas fiber. The change in surface morphology of these composites was studied by scanning electron microscopy (SEM) before and after the friction test. SEM images of friction samples containing aramid pulp corroborated the occurrence of wear through an adhesive wear mechanism, whereas the lapinas fiber–containing composites showed an abrasive wear mechanism.     

Wear mechanism of multiphase friction materials with different phenolic resin matrices

Wear of the brake friction materials with straight phenolic resin, silicon modified phenolic resin, or boron–phosphorous (B–P) modified phenolic resin was investigated. A simple formulation was used to produce friction material specimens and wear tests were carried out using a Krauss type friction tester. Friction stability and wear rate of the three friction materials were compared as a function of temperature up to 400 °C and the mechanisms associated with the wear processes at different temperature ranges were analyzed using Arrhenius type plots and worn surface morphology after tests. The results showed that the wear process below the critical temperature was mainly attributed to the gradual stripping of the heat affected surface layers of the friction material, while the wear rate at elevated temperatures was determined by the detachment of subsurfaces that was caused by the thermal decomposition of the resin. Among the three friction materials investigated in this study, the friction material containing B–P modified resin showed the best wear resistance and friction stability.     

硼酸-桐油双改性酚醛树脂基制动带的摩擦性能研究

对编织型制动带的基体树脂进行热重分析,测试和研究制动带的力学性能、摩擦磨损性能及其在摩擦运行前后的表面形貌。结果表明,采用硼酸-桐油双改性酚醛树脂作为基体树脂,可改善编织制动带的黏接状况,提高制动带的柔韧性,使制动带的相关力学性能及摩擦状况得到明显改善;酚醛树脂的硼酸-桐油双改性可提高树脂的耐热性,有效减少制动带在高温工况下的热分解产物,使摩擦因数能在较宽的温度范围内维持较为理想的数值水平,降低制动带在中、高温下的磨损率,对改善编织型制动带的抗热衰退能力有显著效果。     

Effects of Resin Type and Fiber Length on the Mechanical and Tribological Properties of Brake Friction Materials

In this study, the effects of resin type and fiber length on mechanical properties and friction characteristics of automotive brake materials were studied. Three types of resin, viz. straight phenolic resin (SR), cashew nut shell liquid modified resin (CR), and melamine resin (MR) were used as matrix material. Lapinus with different lengths was used as inorganic fiber. Three series of friction composites composed of nine composites in the form of brake materials were manufactured. Physical, mechanical, and tribological properties of all composites were investigated. The friction tests were performed using a Chase type friction tester. The results showed that both resin type and fiber length played an important role on the mechanical and tribological properties of the friction materials. The highest and the lowest friction coefficient for resin types were recorded for SR and MR composites, respectively, while MR and CR composites showed the highest and the lowest wear resistance, respectively. For the fiber length considered, increasing the fiber length increased the wear resistance of the composites. The coefficient of friction, in general, showed a good correlation with the wear resistance of the composites. But, there was no clear correlation with the mechanical and tribological properties of the composites. The morphological features of worn surfaces and wear debris of the composites were analyzed in order to understand the friction and wear mechanisms of this tribosystem.     

Effect of resin modification on friction and wear of glass phenolic composites

The effect of resin modification on the friction and wear of glass woven roving phenolic composites has been studied. The friction and wear tests were carried out on a purpose built pin-on-disc apparatus. Straight (unmodified) phenolic resin, when chemically modified with poly (vinyl butyral) (PVB) containing 10 wt.% of butyraldehyde, results in improved ductility of the resin and increases the tensile modulus and impact energy of the composite. Modification of the matrix resin with PVB reduces the coefficient of friction and improves the wear resistance of the composite.     

Friction and wear of friction materials containing two different phenolic resins reinforced with aramid pulp

Friction and wear characteristics of automotive friction materials containing two different phenolic resins (a straight novolac resin and a modified novolac resin) were investigated using a pad-on-disk type friction tester. Six different friction materials with different relative amounts of the phenolic resins and aramid pulp were manufactured and tested. Two different test modes were employed to examine the friction characteristics concerning accumulated thermal history (a constant initial temperature test: test mode I) and friction heat (a constant interval test: test mode II). Friction characteristics such as friction stability and wear resistance were changed significantly according to the type of phenolic resins and to the relative amount of the resin and aramid pulp. Friction materials with the modified novolac resin showed better friction stability than those with the unmodified novolac resin. In particular, the friction materials that were reinforced with 10 vol.% of aramid pulp showed substantial improvement on friction stability regardless of the resin type. However, the friction materials with the modified resin showed significant reduction in wear resistance.     

Influence of amount and modification of resin on fade and recovery behavior of non-asbestos organic (NAO) friction materials

Phenol formaldehyde resin is one of the most important ingredients in friction materials that binds the other multiple ingredients firmly. The type and amount of resin in the friction material is very critical for structural integrity of the composite. Present work focuses on the influence of resin percentage and modification of straight phenolic resin by cashew nut shell liquid (CNSL) on fade and recovery behavior of friction composites developed in the laboratory. These composites were based on variation in amount of CNSL modified resin (10, 12.5, and 15 wt.%) keeping other ingredients same. Fade and recovery studies on these composites were done according to ECE R-90 regulation. The friction coefficient (μ) (all types viz. performance, fade, and recovery), extent of fade and recovery, increase in counterface temperature, wear and mechanical properties were significantly influenced by the variation in amount of resin. It was observed that with increase in amount of resin all types of μ decreased and extent of fade increased. Most of the mechanical properties and wear, however, improved with increase in percentage of resin. Since μ is more important for friction materials rather than wear, it was concluded that 10 wt.% CNSL resin was an optimum amount for best friction performance in severe operating conditions. The performance properties of these composites when compared with similar composites based on unmodified resin in earlier work, it was revealed that the modification of phenolic resin by CNSL deteriorated the fade and recovery performance.