聚四氟乙烯填充PA1010的摩擦磨损性能研究

以注塑成型法制备了聚四氟乙烯(PTFE)填充PA1010复合材料,利用M-2000磨损试验机测试了该复合材料与GCr15轴承钢对摩时的摩擦磨损性能,并用扫描电子显微镜(SEM)观察了试样磨损表面形貌.结果表明:PTFE填充PA1010可显著改善尼龙复合材料的摩擦磨损性能.w(PTFE)为25%时,复合材料的摩擦学综合性能最佳.复合材料的摩擦系数和磨损体积随施加载荷、滑动速度的增加分别呈现降低和增加的趋势.在200 N载荷下,复合材料磨损主要为磨粒磨损;在400 N载荷下,磨损表现为黏着磨损和磨粒磨损共同作用.在滑动速度为0.21 m/s时,材料摩擦表面因挤压发生塑性流变,其磨损机理为磨粒磨损;在滑动速度为0.84 m/s,复合材料因热疲劳和应力疲劳发生剥层,磨损机理转变为疲劳剥层磨损.     

对偶表面粗糙度对Nano-SiO2改性PTFE复合材料摩擦学性能的影响

为了研究干摩擦条件下对偶表面粗糙度对纳米粒子填充改性聚四氟乙烯（PTFE）复合材料摩擦磨损及转移膜特性的影响规律,本文采用冷压成型、热烧结的工艺方法制备nano-SiO2填充改性PTFE复合材料;采用LSR-2M型往复摩擦磨损试验机评价了nano-SiO2改性PTFE复合材料与具有三种不同表面粗糙度的对偶钢块（GCr15）之间的摩擦磨损性能;利用光学显微镜（OM）、扫描电子显微镜（SEM）和能谱仪（EDS）分别表征了转移膜及磨屑的形貌、微观结构以及化学成分,从微观角度揭示nano-SiO2改性PTFE复合材料的摩擦转移机理。试验结果表明,纯PTFE及不同含量nano-SiO2填充改性PTFE复合材料的摩擦系数均随对偶钢块表面粗糙度的增大整体呈增大趋势,在粗糙度为Ra0.1的对偶表面上复合材料的摩擦系数随着nano-SiO2含量的增加变化相对较小;在三种不同粗糙度对偶表面上,nano-SiO2的加入均有效降低了PTFE的磨损体积,当填充比例为0.5wt%时复合材料在粗糙度为Ra1.2的对偶面上摩擦学性能最佳,磨合时间约为纯PTFE的1/3（缩短了近10min）,耐磨性较纯PTFE提高了34.1%。由此可见,复合材料中nano-SiO2的含量与对偶表面粗糙度存在一定的协同效应,即nano-SiO2的含量与对偶表面粗糙度具有匹配性,合理的摩擦配副能有效促进复合材料的摩擦转移,并能在对偶表面形成覆盖率高、均匀、连续、表面较粗糙且与摩擦方向趋向一致的转移膜,有利于降低材料的磨损。     

SiC颗粒增强PTFE基复合材料摩擦磨损特性研究

利用冷压烧结法制备了不同含量的SiC颗粒填充聚四氟乙烯(PTFE)复合材料，采用M-200环块试验机进行摩擦磨损试验，研究了SiC颗粒增强PTFE基复合材料在干摩擦条件下的磨损特性，并利用扫描电子显微镜对复合材料的磨损表面形貌进行了观察，对复合材料的磨损机制进行了分析．结果表明：SiC颗粒增强复合材料的耐磨性能显著提高，但其摩擦系数有所增大；随SiC颗粒含量的增加复合材料的磨损机理由粘着磨损占主导逐渐转变为显微切削占主导；复合材料中增强相SiC颗粒有3种流失形式：整体脱落、磨损、碎裂．     

PTFE和MoS_2填充尼龙复合材料摩擦行为研究

以注塑成型法制备了聚四氟乙烯(PTFE)和MoS2填充PA1010复合材料,采用M-2000磨损试验机考察了复合材料与45钢对摩时的摩擦磨损性能,并利用扫描电子显微镜(SEM)分析了PA复合材料磨损表面及其偶件表面转移膜形貌。研究结果表明:PTFE填充PA1010可显著改善尼龙复合材料的摩擦磨损性能。PTFE质量分数为25%时,复合材料的摩擦学综合性能最佳。PTFE和MoS2共同填充PA1010时,复合材料的摩擦因数和磨损率随着PTFE含量的减少、MoS2含量的增加,整体呈现增大趋势,其中PA+20%PTFE+5%MoS2复合材料的减摩抗磨性能较好。在正常工作条件下(0.21-0.42 m/s,100-300 N),PA+25%PTFE复合材料的抗磨性优于相同条件下PA+20%PTFE+5%MoS2复合材料,但PA+20%PTFE+5%MoS2复合材料具有更宽的速度适用范围。PA复合材料的摩擦磨损性能与其在偶件表面形成的转移膜的特性有重要关系,转移膜的厚度大小、分布均匀状况以及和偶件的结合强度都会对复合材料的减摩抗磨性能产生影响。     

Tribological properties and failure analysis of PTFE composites used for seals in the transmission unit

The sealing rings are one of the most important components as the sealing devices in the wet clutch unit of a heavy vehicle. The sealing ring, made from PTFE composites, was subjected to serious wear on the sealing surface, but the mating metal surface only had slight abrasion. A specialized test rig was designed for wear research and failure analysis of the sealing ring. The composition analyses of the ring material, working conditions and wear surface characteristics by visual inspection and tribological properties as well as microscopic analysis with scanning electron microscope was performed to determine the wear mechanism and failure causes. Results revealed that the wear of PTFE composites was characterized by abrasion and adhesion after a certain duration testing, and the wear mechanism changed to thermal fatigue and abrasive wear in the stage of intense wear. The thermal deformation and fatigue were primarily responsible for the rapid wear of the PTFE composites for the sealing rings.     

碳纳米管/铝基复合材料的制备及摩擦性能研究

采用无压渗透法制备了碳纳米管增强铝基复合材料，并对其摩擦性能进行了研究。利用扫描电镜（SEM）观察了复合材料断面的形貌，通过复合材料硬度测量和摩擦磨损实验，研究了不同碳纳米管体积分数对复合材料的硬度及摩擦磨损性能的影响。实验结果表明，碳纳米管均匀地分散于复合材料中，且与铝基体结合良好；碳纳米管的加入增大了复合材料的硬度，且其摩擦系数和磨损率随着碳纳米管体积分数的增大而减小。由于碳纳米管本身具有自润滑和增强作用，碳纳米管的加入极大地改善了铝合金材料的摩擦性能。     

表面处理碳纤维对增强尼龙复合材料性能影响

采用空气氧化法对碳纤维进行表面处理 ,以注塑成型法制备碳纤维增强尼龙 1 0 1 0复合材料 .研究发现表面处理碳纤维可明显提高增强尼龙复合材料的拉伸强度和摩擦学性能 ,其中摩擦系数较未处理碳纤维增强降低了 3 0 %～ 5 0 % ,而耐磨性提高了 2～ 3倍 .用扫描电镜对拉伸断口和磨损表面形貌分析发现 ,表面处理可显著改善碳纤维和尼龙基体间的界面结合性能 .最后对影响表面处理碳纤维增强复合材料性能的作用机理进行了初步分析     

Tribological Properties of Polytetrafluoroethylene Composites Filled with Rare Earths Modified Glass Fibers

1Introduction Polytetrafluoroethyleneisakindofperfectself lubri catingmaterialduetoitsverylowfrictioncoefficient,goodhightemperaturestabilityandchemicalstability.Yetitcannotbeusedasanti wearmaterialalonebecause ofitspoormechanicalproperties,badthermalconductivi tyandhighwearrate.Therefore,variousreinforcement andmodificationofPTFEhavebeentried,andthefric tionandwearpropertiesofPTFEcompositeshavebeen extensivelystudiedbymanyinvestigators[14].Glassfiberexhibitsahightensilestrengthandten sile…     

GF增强尼龙1010复合材料的磨擦学性能研究

制备了玻璃纤维（GF）增强尼龙1010复合材料,在环一块磨损试验机上研究了复合材料的摩擦学性能。结果表明：GF含量对复合材料的摩擦学性能有显著影响,GF质量分数为35％时增强效果较好;随着滑速的增加,GF增强尼龙1010复合材料的摩擦系数和磨损量持续上升。干摩擦下的复合材料磨损以疲劳断裂和粘着为主,且纤维出现磨损、断裂及从基体中剥落的现象。在油润滑下材料向对偶产生轻微的转移,与干摩擦相比复合材料的摩擦系数和磨损量大为降低;水润滑下的尼龙以化学腐蚀磨损和磨粒磨损为主,此时复合材料摩擦系数也有较大程度的降低,但磨损量较干摩擦增大。     

青铜-聚四氟乙烯复合材料温压新工艺

填充聚四氟乙烯以其优异的性能,成为具有广泛应用前景的粒子改性复合材料,在聚四氟乙烯中加入青铜后克服了纯聚四氟乙烯的耐磨性差、热膨胀系数大等缺点,扩大了聚四氟乙烯的应用范围.填充聚四氟乙烯温压成型性能的主要工艺参数是烧结温度、烧结时间、预压压力,常规的压缩模塑成型法,周期长、性能差、表面精度和光洁度不高,本研究的温压成型工艺工序少、周期短、机械性能得到明显提高.     

GF/MoS2改性PTFE密封唇片材料的力学及摩擦学性能

采用玻璃纤维(GF)微粉与MoS₂复合改性聚四氟乙烯(PTFE)密封唇片材料,考察复合材料的力学、干摩擦磨损性能及其磨损机理。结果表明:当GF质量分数为15%时,PTFE/GF试样的回弹率达到最大值92.5%,摩擦因数为0.29,相比纯PTFE有所增加,而磨损率大大降低,仅为1.8×10?6mm3/(N·m);在此基础上,当MoS₂添加量为5%时,PTFE/GF/MoS₂试样的回弹率略有降低,但仍然保持在90%以上,其摩擦因数为0.31,体积磨损率进一步降低到1.25×10?6mm3/(N·m)。磨损面SEM分析表明:纯PTFE呈现出严重的塑性变形和粘着磨损特征,而PTFE/GF主要表现为磨粒磨损行为;适当MoS₂含量的PTFE/GF/MoS₂试样在摩擦过程中磨粒磨损特征消失,仅有非常轻微的粘着磨损行为。     

Tribological Behaviours of PTFE Composites Filled with PEEK and Nano-ZrO_2 Based on Pin-on-Flat Reciprocating Friction Model

Nano-Zr O_2 and PEEK particles were synergistically filled in unfilled PTFE to improve the wear resistance and maintain a relatively low friction coefficient, and the materials were studied using a reciprocating sliding friction and wear tester. In the friction tests, the evolution of various tribological characteristics in both the contact interfaces and debris was observed, and the wear mechanism of the PTFE composites was investigated. The results showed that the wear rate of the PTFE composites synergistically filled with nano-Zr O_2 and PEEK was lower and its friction coefficient was slightly higher than that of the unfilled PTFE; the uniformity and continuity of the transfer film generated by the composite with nano-Zr O_2 and PEEK were the best, and the particle size of the debris was minimal in comparison to that in other sample systems.     

SiC粒径对PTFE/SiCp复合材料耐磨性能的影响

利用机械混合法制备了不同粒径SiCp填充聚四氟乙烯（PTFE）复合材料PTFE／SiCp，并采用M－200型环－块材料磨损试验机在干摩擦条件下对其磨损特性进行了研究，并利用扫描电子显微镜（SEM）及能谱仪对复合材料的磨损表面和摩擦环表面进行了形貌观察及检测。结果表明：SiCp的加入大大提高了PTFE的耐磨性能，SiCp粒径的大小是影响复合材料耐磨性能及磨损机理的重要因素之一。     

碳纳米管耐磨改性MC尼龙及磨耗机理

采用阴离子聚合法制备碳纳米管/MC尼龙复合材料,对其摩擦磨损性能行研究.用扫描电子显微镜观察分析试样磨损表面的形貌,分析磨耗机理.实验结果表明:碳纳米管加入量越多,摩擦系数越小;在磨损时间相同的情况下,碳纳米管加入量为0.3%时,磨耗指数最小;磨损时间较长试样的磨耗指数比磨损时间少的试样磨耗指数小.磨损时间较少时,主要发生粘着磨损;当磨损时间较长时,主要发生磨粒磨损.在有载荷条件下磨损比较严重,这种情况下发生的是粘着磨损和磨粒磨损.在无载荷条件下主要发生的是粘着磨损.在耐磨性提高的同时,力学性能也得到一定的提高.     

纳米SiO2填充尼龙PA1010的摩擦磨损性能实验研究

用纳米 Si O2 填充 PA1 0 1 0制备了尼龙复合材料 ,并用 MM- 2 0 0磨损试验机对尼龙复合材料与 45钢在干摩擦条件下的摩擦磨损实验进行了实验 .研究表明 ,纳米 Si O2 填充 PA1 0 1 0大幅度提高了尼龙复合材料的耐磨性 ,降低了摩擦系数 .纳米 Si O2 填充量在 1 0 %左右时 ,尼龙复合材料达到最低摩擦系数 0 .32和最低磨损量 0 .2 mg,磨损量比纯 PA1 0 1 0降低了 60多倍 ,摩擦系数降低了 1倍 .对纳米 Si O2 填充尼龙的磨损机理研究发现 ,纳米 Si O2 填充尼龙复合材料的磨损机理受滑动速度和接触载荷影响比较大 .当摩擦副 PV值小于 60 Nm/ s时 ,尼龙复合材料的磨损机理主要是切削和粘着磨损 .当摩擦副 PV值大于 60 Nm/ s时 ,磨损机理转变为疲劳剥层或熔融流变 ,导致磨损量急剧增长 .     

Wear performance of Ni/ZrO<Subscript>2</Subscript> infiltrated composite layer

The Ni/ZrO2 was used as raw materials to fabricate the surface infiltrated composite layer with 1-4 mm thickness on cast steel substrate through vacuum infiltrated casting technology. The microstructure indicated that the infiltrated composite layer included surface composite layer and transition layer. Wear property was investigated under room temperature and 450 ℃. The results indicated that the abrasion volume of substrate was 8 times that of the infiltrated composite layer at room temperature. The friction coefficient of infiltrated composite layer decreased with the increasing load. The wear resistance of infiltrated composite layer with different ZrO2 contents had been improved obviously under high temperature. The friction coefficient of infiltrated composite layer was decreased comparing with that at room temperature. The oxidation, abrasive and fatigue abrasion was the main wear mechanism at room temperature. Oxidation abrasion, fatigue wear and adhesive wear dominated the wearing process under elevated temperature.     

SiC颗粒填充PTFE复合材料耐磨性能的研究

利用M－200型环一块大材料磨损试验机，对机械混合法制备的SiC陶瓷颗粒填充聚四氟乙烯（PTFE）复合材料在干摩擦条件下的磨损特性进行了研究，并利用扫描电子显微镜(SEM)对TFE复合材料的磨损表面形貌进行了观察。结果表明SiC颗粒入大大提高了PTFE的耐磨性能，颗粒的添加量、磨损载荷、磨损温度影响复合材料耐磨性能的重要因素。     

PTFE基金属复合材料的摩擦磨耗性能研究

用热啧涂法在低碳钢基体上分别形成Al Bronze和Mo薄膜,再通过热烧结的方法在薄膜表面沉积PTFE层,制备了一种PTFE基金属复合材料.通过Type32型摩擦磨损试验机考察了样品在干摩擦条件下的磨耗性能,用光学显微镜观察了实验过程中样品表面形貌变化.结果表明,由AlBronze喷涂形成的PTFE基金属复合材料的磨耗性能优于由Mo复合形成的复合材料,这可通过XRD分析其过程中发生的物理化学变化来解释.     

纳米填料增强UHMWPE–橡胶水润滑摩擦学性能

为了研究水润滑条件下试验载荷和速度对纳米填料（Nano-SiC）改性超高分子量聚乙烯（UHMWPE）/橡胶复合材料摩擦学性能的影响,通过高温混炼、热压成型制备Nano-SiC辅以聚四氟乙烯（PTFE）填充改性UHMWPE/橡胶复合材料。采用MRH-3型环-块摩擦实验机探究四种不同载荷条件下改性复合材料的摩擦磨损性能,采用光学显微镜（OM）、扫描电子显微镜（SEM）和非接触光学三维轮廓仪对试样微观磨损表面形貌分析,从微观层面探究改性复合材料的摩擦机理。试验结果表明：在定载变速条件下,速度由0.02m/s升到3.59m/s时,改性复合材料的动摩擦系数波动幅度与静摩擦系数均呈现大幅下降趋势,粘-滑现象（Stick-Slip Phenomenon）减弱,摩擦系数波动归于平稳;试验载荷和纳米粒子含量的变化与试样摩擦磨损程度呈负相关,在水润滑条件下,随着纳米粒子含量增加,摩擦系数与磨损率均出现明显降低,填充比例为5%的复合材料摩擦学性能最佳,摩擦系数整体较UHMWPE/橡胶材料降低35%,磨损率降低46.6%,磨损表面形貌也随之发生改变;随着载荷的增加,复合材料的磨损率从1.25×10-6mm3/(Nm)降至0.4×10-6mm3/(Nm)。Nano-SiC的含量与工况载荷压力对摩擦磨损均存在一定影响,即填充适量Nano-SiC的UHMWPE/橡胶复合材料与一定工况压力下的对偶钢环组成的摩擦配副能改善摩擦环境,减轻粘-滑现象,有利于减小材料的磨损。     

Tribological Properties of Polyvinyl Mcohol Hydrogel Reinforced with Nanometer Hydroxy Apatite

As a potential artificial cartilage material,the friction and wear properties of nano-hydroxy apatite(HA)particles filled poly(vinyl alcohol)hydrogel(PVA-H)composites sliding against stainless steel disk under water lubrication condition were studied by using a four ball tester.The worn surfaces were investigated by using a scanning electron microscope(SEM)to determine the wear mechanisms.Experimental results show that filling HA to PVA-H will slightly increase the friction coefficient of composites with the increasing of HA content under water lubrication condition.Meanwhile,HA particles can greatly reduce the wear mass loss of the PVA-H composites and enhance the load carrying capacity,the wear loss of the 1 wt% HA reinforced PVA-H composites can be decreased by 30 percent under 2.0 MPa to 50 percent under 0.5 MPa contact pressure.We also found that 2 wt% HA content of composites increase the wear mass loss under the same condition.SEM examination shows that the worn surface of low HA containing(1 wt%)composites are much smoother than that of pure PVA-H or high HA containing(2 wt%)composites under 1.5 MPa contact pressure.It is also found that there are big hole and big reunited HA particles in the surface of 2 wt% HA containing composites,which leads to deterioration of the surface of samples under higher loads in water lubrication.These results may be useful in the tribological design of artificial articular cartilage material.