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室温及气氛条件下铜基自润滑复合材料的摩擦磨损性能研究 总被引:3,自引:0,他引:3
采用粉末冶金法制备了3种铜基自润滑复合材料,分别考察了它们在室温及气氛条件下的摩擦磨损性能,通过对复合材料的力学性能和磨痕表面形貌、成分的分析,探讨其摩擦磨损机制.结果表明:Cu-9%石墨、Cu-4.5%石墨-4.5%MoS2、Cu-9%MoS2复合材料的密度、硬度和抗弯强度值都依次增大;室温条件下,因石墨与Cu的硫化物协同润滑作用,Cu-4.5%石墨-4.5%MoS2复合材料的摩擦磨损性能最好;气氛条件下,因Cu的硫化物发挥了其自润滑作用,Cu-9%MoS2复合材料表现出最佳的减摩耐磨性能,而Cu-4.5%石墨-4.5%MoS2复合材料次之;铜基自润滑材料的基体强度与固体润滑膜的覆盖率,是影响摩擦磨损机制转变的关键因素. 相似文献
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石墨铝基自润滑材料的制备及性能表征 总被引:1,自引:0,他引:1
以石墨为固体润滑剂,铝为基体材料,添加硅、铜、铁等元素作为强化成分,添加Cr3C2、粉煤灰来提高自润滑材料的耐磨性,通过液态铸造法制备铝基自润滑材料。借助MM-200磨损试验机研究不同石墨含量以及粉煤灰的添加对铝基复合材料摩擦磨损性能的影响;在Olympus金相显微镜下观察材料显微组织;用S-3000N扫描电子显微镜对材料拉伸断口和磨损表面进行观察。结果表明:随着石墨含量的增加,摩擦因数逐渐降低,磨损率逐渐升高,抗拉强度、硬度都逐渐降低;粉煤灰的加入使得初生硅得到细化,自润滑材料的强度上升,摩擦因数得到进一步的改善。 相似文献
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Ti3SiC2作为一种新型的金属陶瓷材料,具有良好的导热性、耐腐蚀性与高温抗氧化性。探究在动车组粉末冶金闸片中应用Ti3SiC2替代石墨作为润滑相对摩擦材料性能的影响。在粉末冶金闸片摩擦材料中加入不同含量的Ti3SiC2替代石墨,观察摩擦表面氧化膜的变化,分析Ti3SiC2加入量对摩擦材料力学性能和摩擦磨损性能的影响。结果表明:随着Ti3SiC2替代石墨加入量的增加,摩擦材料的剪切强度逐渐提高,使用Ti3SiC2替代全部石墨(质量分数18%)时,剪切强度提高了6倍;在350 km/h高速制动时,摩擦表面形成了氧化膜,随着Ti3SiC2加入量的增加,氧化膜的覆盖面积不断增大并呈现连续分布状态;当Ti3SiC2质量分数大于9%后,在高速制动时摩擦材料的摩擦磨损量和摩擦因数明显降低,Ti3SiC2替代全部石墨后摩擦因数降低了36.8%,摩擦磨损量降低了67.5%。 相似文献
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采用冷压-烧结-复压的方法在900℃下制备不同铝含量的铜基石墨复合材料,研究在干、湿2种摩擦条件下铝含量对复合材料摩擦学性能与磨损机制的影响。结果表明:铝含量增加,有利于提高复合材料的硬度和抗弯强度,但复合材料相对密度呈现先增后降的趋势;在干、湿摩擦条件下,较高的铝含量均使得复合材料耐磨性能得到极大提高,这是因为高铝含量的复合材料具有更高的强度,能有效抵抗微凸体犁削,并且能支撑保护更多石墨,避免金属基体与对偶件直接接触;在铜基石墨复合材料中添加铝后材料的强度增大,使剥落磨损和磨粒磨损减弱,氧化磨损逐渐加强,且湿摩擦时因水的作用使氧化磨损更加剧烈。 相似文献
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为提升石墨材料在高强度机械密封工况下的机械性能和密封性能,以煤炭加工的附加值产品(煤焦和沥青)为原料制备多孔石墨材料,然后通过高压浸锑制备煤基浸锑石墨密封材料;比较浸渍前后石墨材料的机械性能、微观结构差异、元素组成变化、摩擦磨损性能,分析浸渍锑后石墨材料性能的增强机制。结果表明:高压浸锑后石墨材料的机械强度和耐磨性能得到明显提升,其中密度增加了26.6%,抗压强度增加了114.3%,硬度增加了63.3%,气孔率下降了94%,绝对磨损量减少89.3%,平均摩擦因数降低了46.4%。高压浸锑后石墨材料中的孔隙被金属锑填充,并连接在一起形成条状,在摩擦磨损过程中充当骨架作用,从而提高石墨材料的抗磨性能;在浸锑石墨密封材料,微细网状的金属充填物可以减少材料的磨粒磨损,从而维持润滑膜的稳定,因而其可以作为高温等恶劣工况下的密封材料使用。 相似文献
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为改善铜锰铝合金的烧结性能,并提高其在干摩擦下的摩擦磨损性能,以铜包石墨作为自润滑相加入到铜锰铝合金中,采用等离子真空压力烧结方法制备铜锰铝/石墨复合材料,分析铜包石墨含量对复合材料的密度、硬度的影响,探讨不同复合材料在干摩擦和油润滑条件下的摩擦磨损性能.结果表明:相比真空和氢气还原气氛下的烧结方式,等离子体烧结铜锰铝... 相似文献
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Effect of electrical current on the tribological behavior of the Cu-WS2-G composites in air and vacuum 总被引:1,自引:0,他引:1
As the traditional graphite-based composites cannot meet the requirement of rapid developing modern industry, novel sliding electrical contact materials with high self-lubricating performance in multiple environments are eagerly required. Herein a copper-based composite with WS2 and graphite as solid lubricant are fabricated by powder metallurgy hot-pressed method. The friction and wear behaviors of the composites with and without current are investigated under the condition with sliding velocity of 10 m/s and normal load of 2.5N/cm 2 in both air and vacuum. Morphologies of the worn surfaces are observed by optical microscope and compositions of the lubricating films are analyzed by XPS. Surface profile curves and roughness of the worn surfaces are obtained by 2205 surface profiler. The results of wear tests show that the friction coefficient and wear volume loss of the composites with current are greater than that without current in both air and vacuum due to the adverse effects of electrical current which damaged the lubricating film partially and roughed the worn surfaces. XPS results demonstrate that the lubricating film formed in air is composed of oxides of Cu, WS2 , elemental S and graphite, while the lubricating film formed in vacuum is composed of Cu, WS2 and graphite. Because of the synergetic lubricating action of oxides of Cu, WS2 and graphite, the composites show low friction coefficient and wear volume loss in air condition. Owing to the fact that graphite loses its lubricity which makes WS2 become the only lubricant, severe adhesive and abrasive wear occur and result in a high value of wear rate in vacuum condition. The formation of the lubricating film on the contact interface between the brush and ring is one of the factors which can greatly affect the wear performance of the brushes. The low contact voltage drop of the composites in vacuum condition is attributed to the high content of Cu in the surface film. This study fabricated a kind of new sliding electrical contact self-lubricating composite with dual-lubricant which can work well in both air and vacuum environments and provides a comprehensive analysis on the lubrication mechanisms of the composite. 相似文献
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研究不同摩擦体系下法向载荷对浸渍石墨的摩擦磨损特性的影响,采用扫描电子显微镜和激光共聚焦显微镜分别表征摩擦表面磨痕形貌、磨痕轮廓,对浸渍石墨与对偶球(GCr15钢球和Si3N4陶瓷球)的摩擦磨损情况与机制进行评估分析。结果表明:磨损痕迹随着施加载荷的增加而加深加宽,磨损率与法向载荷呈负相关,而摩擦因数、磨损体积则与法向载荷呈正相关;小载荷作用下石墨的磨损机制为黏着磨损和磨粒磨损,大载荷下则主要表现为黏着磨损、氧化磨损以及疲劳磨损;GCr15/石墨摩擦副相比于Si3N4/石墨摩擦副磨损率较低,在摩擦过程中形成完整、连续性更好的“第三体”转移膜减轻了磨损,对石墨基体起到保护作用。 相似文献
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Tribological performance of graphite containing tin lead bronze-steel bimetal under reciprocal sliding test 总被引:1,自引:0,他引:1
Liu Ru-Tie Xiong XiangChen Fu-Sheng Lu Jin-zhongHong Li-Ling Zhang Yi-Qing 《Tribology International》2011,44(2):101-105
As a solid self-lubricating material to serve under heavy load and low velocity, graphite containing tin lead bronze-steel bimetal composites were prepared using the powder metallurgy (P/M) technique. Effects of graphite content on tribological performance under reciprocal sliding were studied using the UMT-2MT tribo-meter. The optimal performance of average friction coefficient, maximum friction coefficient, friction coefficient amplitude and wear resistance can be achieved at the graphite content of ∼3 wt%. Appropriate graphite content and hardness are the two most crucial factors to achieve a good quality lubricating film on the worn surface and hence the desired solid lubrication performance. 相似文献
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为了探讨聚酰亚胺黏结石墨基固体润滑涂层在油介质中的摩擦学性能及其作用机制,采用MHK-500型摩擦磨损实验机对聚酰亚胺黏结石墨基固体润滑涂层在4种油介质(RP-3煤油、0#柴油、液体石蜡和SG 15W-40机油)中的摩擦磨损性能进行评价,并对其机制进行初步的探讨。结果表明:与干摩擦相比,涂层在4种油介质中的摩擦学性能都有显著提高,其中在柴油介质中涂层的抗磨性能提高最为突出,可能的原因是中等黏度的柴油介质在摩擦界面能形成足够厚的油膜,又能对涂层进行有效的冷却;同种油介质中,涂层在高速(2.56 m/s)、低载(1 120 N)下的耐磨性能明显优于低速(1.54 m/s)、高载(2 120 N)下的耐磨性能。 相似文献
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在M-200摩擦试验机上进行不同含量石墨填充PEI基复合材料的摩擦磨损试验,利用扫描电子显微镜分析了断口和磨损表面的显微结构,并分析了磨损机制。考察了表面硬度随含量填充量的变化规律。试验结果表明:石墨在复合材料基体中呈片状结构,磨损过程中易形成转移膜,从而改善了摩擦磨损情况,其中填充质量分数10%石墨的PEI基复合材料摩擦因数最低,填充30%石墨的复合材料磨损率最低,材料表面硬度随着填充石墨含量的增加而降低,石墨填充量在5%~30%之间表面硬度下降平缓,当填充量超过30%时,材料表面硬度下降剧烈。 相似文献
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传统油或脂润滑剂在极端工况环境下无法满足碳钢类零件的减摩要求,采用干膜润滑剂是提高极端工况环境下碳钢表面摩擦磨损性能的可行性方法。采用超声波分散方法制备以石墨粉末为基体的干膜润滑剂,使用压力喷涂技术使其沉积在碳钢试件表面,在端面摩擦试验仪中开展干摩擦和石墨干膜润滑剂润滑下摩擦磨损性能对比性试验研究。试验结果表明:石墨干膜润滑剂在碳钢表面的沉积效果较好,沉积的石墨干膜润滑剂具有较好的润滑性能,可以有效地保护碳钢表面不被过度磨损;喷涂石墨干膜润滑剂的碳钢试件的工作寿命随着压力载荷和主轴转速的增大而缩短,负载和滑动速度的联合作用会加速涂层向稳定方向的过渡;磨损过程中形成的微观润滑剂颗粒会形成颗粒流润滑,适当添加石墨颗粒粉末可能会延长润滑剂正常发挥减摩作用的时间。制备的石墨干膜润滑剂为碳钢在极端工况环境下的减摩提供了支持。 相似文献
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Copper matrix composites containing graphite and tungsten disulfide were prepared and tested under the loads of 1–5 N to investigate their friction and wear behaviors. The microstructure, worn surfaces, and cross section of worn subsurfaces were observed, and the lubricating films formed on the worn surfaces were analyzed. It is found that the Cu–24 vol% WS2 composite presents a higher mechanical performance and lower wear rate compared to the Cu–24 vol% graphite composite with same volume fraction of solid lubricant. This could be attributed to the high-strength chemical bonding of the interface between WS2 and the copper matrix. The high-strength interfacial bonding also helps prevent plastic deformation and the formation of cracks at the worn subsurfaces of the composites. The amount of lubricant on the outmost worn surfaces is significantly higher than that in the composite. The lubricating film of WS2 with relatively high thickness provides a low friction coefficient to the composites. 相似文献