三维连续网状多孔陶瓷增强ZL102复合材料的摩擦磨损特性

对铸造铝基三维连续网状多孔陶瓷复合材料在干摩擦和油润滑条件下的耐磨性进行了较细致的分析,并对影响该复合材料滑动磨损行为的因素进行了讨论。结果表明：无论在干摩擦还是油润滑条件下,复合材料均比基体合金耐磨,尤其是高载时,复合材料的耐磨性能更突出地显示出来。     

润滑状态对C/C复合材料摩擦磨损特性的影响

在M-2000型摩擦磨损实验机上,对3种C/C复合材料与40Cr钢配副分别在干态、水润滑、油润滑3种条件下的摩擦磨损行为进行了研究.结果表明:在3种润滑条件下,干态摩擦试样的摩擦系数最大,体积磨损最小;基体炭为树脂浸渍炭的试样在3种试样摩擦系数最高,约为0.141～0.205;水润滑时试样的摩擦系数最小,为0.05～0.10,但体积磨损最大,最高可达7.75 mm3油润滑时试样的摩擦系数和体积磨损均介于干态和水润滑之间;干摩擦时,试样的摩擦系数随着载荷增加而缓慢降低,水润滑和油润滑的摩擦系数则随着载荷的增加而先增加后减少;干态摩擦时材料表面形成了完整的摩擦膜,水润滑和油润滑条件下摩擦膜很薄且不完整;所有润滑条件下试样均以磨粒磨损或犁削磨损为主.     

Sip/ZA40复合材料磨损性能研究

采用磨损试验研究了干磨擦和油润滑摩擦条件下,硅含量对含硅高铝锌基复合材料磨损性能的影响。应用扫描电子显微镜分析了复合材料磨面的形貌特征。结果表明,含硅高铝锌基复合材料的耐磨损性能优于基体合金;在油润滑条件下,硅含量越高,复合材料的耐磨性能越好;在干摩擦条件下,硅含量为4.5％复合材料的耐磨性能优于其它试验材料。含硅材料的磨损机理是微切削磨损、表面脱落和磨粒磨损的综合作用。     

FeS/铜基复合材料的摩擦学性能

通过粉末冶金方法制备含FeS的铜基复合材料。采用MM-200型摩擦磨损试验机,以不锈钢为对偶件,分别在干摩擦和油润滑条件下对其摩擦磨损性能进行检测,利用SEM、XPS等技术对磨损表面进行观察和分析。结果表明:干摩擦条件下,材料中的FeS可以逐渐转移、附着在摩擦副表面形成固体润滑膜起减摩、抗粘着作用;油润滑条件下,FeS含量较低时,润滑油膜和FeS固体润滑膜可以起协同润滑作用,随着FeS含量的增多,协同润滑效果越来越明显;FeS含量较高时,铜基复合材料的强度、硬度较低,而且FeS颗粒含有较多微观孔隙,使摩擦副间的润滑油膜稳定性变差而易破裂,复合材料的摩擦磨损性能降低。     

Ti(C,N)颗粒增强铁基复合材料磨损性能的研究

以45钢、钛铁、生铁等为主要原料,在大气环境下、利用中频感应电炉、通过添加含氮附加物、采用原位反应铸造法制备了Ti(C,N)颗粒增强铁基复合材料。研究了所制备复合材料的油润滑摩擦磨损性能、干摩擦磨损性能以及冲击磨料磨损性能。结果表明,在有润滑和无润滑条件下的干摩擦,复合材料的耐磨性能都远大于正火45钢;在中、低冲击工况下,复合材料磨料磨损性能优于高锰钢和高铬铸铁。     

原位反应TiCp/Fe、VCp/Fe复合材料的油润滑摩擦及干摩擦磨损性能研究

对复合材料TiCp/Fe、VCp/Fe的油润滑摩擦磨损性能及干摩擦磨损性能进行了研究，对比在不同条件下复合材料的耐磨性，以及在工况相同的条件下，对比原位反应铁基复合材料与正火45钢的耐磨性。实验结果表明，在有润滑的条件下，由于VC陶瓷颗粒、TiC陶瓷颗粒对复合材料基体的增强作用，复合材料的耐磨性远大于正火45钢的耐磨性，而VCp／Fe复合材料的耐磨性比TiCp／Fe复合材料的耐磨性更好。在无润滑条件下，铁基复合材料的耐磨性也比正火45钢的耐磨性大得多。在载荷较大的条件下，TiCp／Fe复合材料的耐磨性比VCp／Fe复合材料的耐磨性更好。     

网状陶瓷复合材料的滑动磨损行为

研究了三维连续网状多孔陶瓷复合材料在干摩擦条件下的滑动磨损行为。结果表明：复合材料的耐磨性优于基体合金;复合材料对磨环的磨损量大于基体合金对磨环的磨损量,但复合材料摩擦副的总磨损量比基体合金摩擦副的小。     

镀锌板的摩擦磨损特性及微观机理研究

采用UMT-2磨损试验机研究镀锌板在干摩擦和油润滑条件下的摩擦磨损特性。运用三维形貌仪WYKONT11观察磨痕、表面粗糙度和表面形貌。对镀锌层的化学成分和显微硬度进行分析;对镀锌板的摩擦磨损机理进行讨论。结果表明:在干摩擦条件下,镀锌板的磨损经历了三个阶段,即磨合磨损,磨粒磨损和粘着磨损。与此同时,锌镀层发生脱落直至完全失去效用。在润滑条件下,良好的润滑减少了摩擦磨损,有助于保护镀锌层。     

油润滑条件下摩擦磨损材料的研究进展

总结了油润滑条件下合金、陶瓷、聚合物等材料体系的摩擦与磨损特性。分析各材料的摩擦磨损机理,综述了其在不同载荷、不同滑动速度下磨损率、摩擦系数的变化,为改进零件摩擦行为以及有效降低磨损损耗提供了可行性的理论依据。总结了不同材料体系下摩擦材料的研究进展,并对此类材料的发展前景进行了展望。     

锡对铸造铝-石墨颗粒复合材料摩擦性能的影响

采用M-200摩擦磨损试验机,对加入固体润滑剂锡的铸造铝-3%石墨颗粒复合材料的摩擦性能进行试验研究,研究表明:锡和石墨具有优越的协同润滑效应,加锡可极大提高铝-石墨颗粒复合材料的减摩性能,使有润滑的摩擦系数达到0.004～0.005。同时锡和石墨的协同润滑作用存在最佳配合,在本试验条件下,加约7%的锡时,协同润滑效应最佳。加锡不能改善干摩擦时铝-3%石墨颗粒复合材料的耐磨性,但能极大提高有润滑时复合材料的耐磨性。并对加锡的铝-石墨颗粒复合材料的磨损机理进行了初步研究,其在干摩擦时的磨损机理为粘着迁移、粘着磨损和磨料磨损,在半干摩擦时的磨损机理为疲劳磨损和磨料磨损。     

硅酸铝短纤维增强Al-12Si合金复合材料的磨损行为

用挤压铸造法制备了低体积分数（３％～７％）的硅酸铝短纤维增强Ａｌ１２Ｓｉ合金复合材料,并利用销盘磨损试验机研究了材料在干摩擦条件下的磨损行为。磨损试验结果表明：硅酸铝短纤维加入到Ａｌ１２Ｓｉ合金明显提高抗磨损能力,随纤维体积分数的增加该复合材料的耐磨性逐渐增强。金相观察和测试表明：基体合金和复合材料的磨损区由硬化层和变形层组成,断裂的ＡｌＳｉ共晶相沿滑动方向重新分布排列形成了硬化层;而复合材料硬化层由于破断的硅酸铝纤维和破碎的ＡｌＳｉ共晶相的共同作用,使该硬化层硬度高于基体合金硬化层的硬度,从而使复合材料表现出优异的耐磨性。并根据试验结果提出了基体合金和复合材料的磨损机制模型     

Wear and transfer characteristics of carbon fiber reinforced polymer composites under water lubrication

The tribological characteristics of carbon fiber reinforced polymer composites under distilled-water-lubricated-sliding and dry-sliding against stainless steel were comparatively investigated. Scanning electron microscopy (SEM) was utilized to examine composite microstructures and modes of failure. The typical chemical states of elements of the transfer film on the stainless steel were examined with X-ray photoelectron spectroscopy (XPS). Wear testing and SEM analysis show that all the composites hold the lowered friction coefficient and show much better wear resistance under water lubricated sliding against stainless steel than those under dry sliding. The wear of composites is characterized by plastic deformation, scuffing, micro cracking, and spalling under both dry-sliding and water lubricated conditions. Plastic deformation, scuffing, micro cracking, and spalling, however, are significantly abated under water-lubricated condition. XPS analysis conforms that none of the materials produces transfer films on the stainless steel counterface with the type familiar from dry sliding, and the transfer of composites onto the counterpart ring surface is significantly hindered while the oxidation of the stainless steel is speeded under water lubrication. The composites hinder transfer onto the steel surface and the boundary lubricating action of water accounts for the much smaller wear rate under water lubrication compared with that under dry sliding. The easier transfer of the composite onto the counterpart steel surface accounts for the larger wear rate of the polymer composite under dry sliding.     

Role of Al2O3 fiber in eutectic Al-Si alloy composites

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Tribological performance of hybrid filtered arc-magnetron coatings. Part II: Tribological properties characterization

Nano-structured coating architectures were developed to provide a best blend of corrosion and wear resistance for high chromium content steels used in aerospace bearing and gear applications. A hybrid filtered arc-magnetron deposition process was employed to deposit functionally graded, multilayered and nanocomposite TiCrN/TiCrCN + TiBC cermet coatings on carburized steel substrates. Coatings exhibited excellent adhesion to the carburized surfaces and had hardness in the range of 23-25 GPa. Tribological properties of the coatings were characterized by: pin-on-disk COF, lubricated sliding, reciprocating sliding, and 3 ball half thrust bearing tests in dry and lubricated environments at high contact stresses. Both polyester and perfluoropolyalkylethers (PFPAE) based lubricants were used to evaluate coating performance with neutral and chemically aggressive lubrication. Sliding friction and reciprocating sliding wear tests were performed using modified disk-on-ring and point-on-disk arrangements, respectively. Contact stresses were estimated using the Hertzian contact formula (sliding friction), and through direct measurements of contact areas by SEM (reciprocating sliding). Low-speed thrust bearing high load rolling contact was evaluated at 350 °C, using Si₃N₄ balls and PFPAE-based lubricant, at contact stresses of ∼ 3.2 GPa. Aggressive corrosion testing was performed on coated samples using MIL-STD-810F “salt-fog” testing. Wear and corrosion behavior was investigated using SEM/EDS, EDX, AFM, profilometry, and optical microscopy. The influence of coating architecture on wear properties was investigated. Multifold improvements in the surface dry and lubricated wear life, reduction of the dry friction coefficient, prevention of corrosion attack from the products of PFPAE lubricant degradation, and improvement of salt-fog corrosion resistance are demonstrated.     

燃烧合成Cr-(Al,Cr)2O3金属陶瓷的耐磨性能

用热爆燃烧合成法结合熔体施压致密化,制备了相对密度约90％的Cr-（Al,Cr）2O3金属陶瓷,金属Cr颗粒均匀弥散分布于陶瓷板片间或板片内,尺寸可达200nm左右．研究了金属陶瓷的耐磨性能．结果表明,干摩擦条件下,金属陶瓷具有优良的耐磨性能;磨损体积与稀释剂Al2O3加入量和过量Cr2O3的含量有关,两者合理搭配可使Cr-（Al,Cr）2O3的磨损体积小于粉末烧结氧化铝陶瓷的磨损体积．磨损机理主要是块状剥落．油润滑后,147N载荷下,金属陶瓷经6000m滑动距离仍基本无磨损体积损失;随载荷提高,磨损体积有所增大,但仍比Cr12MoV钢小一个数量级以上．     

激光熔覆TiC增强FeAl金属间化合物基复合材料涂层磨损性研究

利用激光熔覆技术在1Cr18Ni9Ti奥氏体不锈钢表面制得了以TiC为增强相、以FeAl 金属间化合物为基体的耐磨复合材料涂层，研究了激光熔覆。FiC／FeAl复合材料涂层在干滑动磨损条件下的耐磨性能及磨损机制。结果表明：随着载荷和滑动速率的增加，TiC／FeAl金属间化合物基复合材料涂层的磨损速率增加，其磨损机制随着载荷的增加逐渐由磨料磨损向粘着磨损转变；激光熔覆层中TiC体积分数的增加，一方面提高了涂层的磨料磨损抗力，另一方面降低了熔覆层表面与对磨材料之间的粘着倾向，提高了TiC／FeAl涂层的滑动磨损性能。激光熔覆TiC/FeAl金属间化合物基复合材料涂层具有优异的耐磨性能并随TiC体积分数的增加而提高。     

Surface finish effect on dry sliding wear behavior of thermally oxidized commercially pure zirconium

The effect of surface polishing on the wear behavior of thermally oxidized commercial pure zirconium (CP-Zr) under dry sliding conditions was investigated. Surface ground CP-Zr with a roughness of 0.21 μm (R_a) was thermally oxidized (TO) at 650 °C for 6 h. After TO, some samples were polished to smoothen the surface with a finish of 0.04 μm (R_a). The response of the polished and unpolished TO samples to dry sliding wear was investigated under unidirectional sliding conditions. The results show that surface polishing after TO affects the dry sliding wear behavior of TO CP-Zr in several aspects, including coefficient of friction, wear rate, crack formation and oxide layer breakdown. In particular, it is found that smoothening the TO surface favors the formation of semi-circular cracks in the wear track and accelerates oxide layer breakdown during dry sliding. A slightly rough TO surface helps to reduce the tendency of the oxide layer towards cracking and to increase the wear resistance at high contact loads. The mechanisms involved are discussed in terms of asperity contacts, crack formation, propagation and final fracture.