蒙脱土/聚酰亚胺复合材料摩擦磨损性能研究

通过原位聚合法制备蒙脱土/聚酰亚胺纳米复合材料,考察蒙脱土含量对复合材料摩擦性能、力学性能以及热稳定性的影响, 并用扫描电子显微镜观察分析复合材料磨损表面,分析磨损机制。结果表明：蒙脱土的加入能够改善复合材料的热稳定性;随着蒙脱土含量的增加,复合材料的拉伸强度呈现下降的趋势,但弹性模量有显著的增加;添加适量的蒙脱土,可以有效地改善聚酰亚胺复合材料的摩擦学性能;随着蒙脱土含量的增加,聚酰亚胺复合材料的磨损机制由黏着磨损转变为磨粒磨损。     

聚酰亚胺复合材料与不同金属间干滑动时的摩擦学性能

采用MPX-2000型摩擦磨损试验机研究了聚四氟乙烯和二硫化钼填充聚酰亚胺复合材料在干滑动摩擦条件下与45钢、镍铬合金、铜和铝对磨时的摩擦磨损性能,并利用扫描电子显微镜和光学显微镜分析了复合材料及对偶件的磨损表面形貌。结果表明:复合材料与铝对磨时的摩擦因数和磨损率最低,分别约为与钢摩擦时的43%和49%;摩擦后铝表面形成均匀连续的转移膜,45钢、镍铬合金和铜的表面没有形成有效转移膜,因此复合材料的摩擦因数较大;复合材料与不同金属材料摩擦时的磨损机理主要是粘着磨损与疲劳磨损。     

碳纤维增强尼龙1010复合材料的摩擦磨损性能及磨损机理研究

以注塑成型法制备了尼龙1010及碳纤维(CF)增强尼龙1010复合材料，研究了CF含量和载荷对材料摩擦学性能和磨损机制的影响。结果表明，CF的加入可显著改善尼龙的摩擦学性能，以体积分数为20％的CF增强尼龙1010复合材料的耐磨性能最好。较低的CF含量下复合材料磨损表面主要受到对偶钢环上微凸峰的切削和犁沟作用，较高载荷时发生了热疲劳剥层磨损；随着CF含量增加，复合材料表面在较高载荷时产生明显疲劳断裂，并使对偶钢环产生较剧烈磨损。     

水润滑条件下聚甲基丙烯酸甲酯/有机改性蒙脱土复合材料摩擦磨损性能研究

采用2种有机改性蒙脱土(OMMT,TJ-2型和KH-V6型),研究了乳液插层法制备的2种聚甲基丙烯酸甲酯(PMMA)/OMMT复合材料在水介质作用下的摩擦磨损性能,并用扫描电子显微镜观察分析了复合材料的磨损表面。结果表明:2种PMMA/OMMT复合材料的摩擦因数和磨损率都随OMMT含量的增加先减小后增加。当OMMT质量分数为5%时,2种复合材料的磨损率最小,约为PMMA的55%,当OMMT质量分数为4%时,2种复合材料的摩擦因数最小,约为PMMA的68%。此外,2种复合材料的磨损机制也基本相同,随着OMMT含量的增加,主要磨损形式依次是粘着磨损、磨粒磨损和疲劳磨损与磨粒磨损的混合磨损形式。     

纳米SiO2对火焰喷涂尼龙1010涂层干摩擦磨损性能的影响

为了探讨纳米SiO2(n-SiO2)对火焰喷涂尼龙(PA)1010涂层干摩擦磨损性能的影响,采用MRH-3型环-块摩擦磨损试验机对不同n-SiO2含量的尼龙1010涂层的干摩擦磨损性能进行了测试;并利用扫描电子显微镜(SEM)对复合涂层的磨损表面进行观察,以探讨n-S iO2对火焰喷涂尼龙1010涂层摩擦磨损性能的影响机制。结果表明:n-SiO2的加入能明显提高尼龙涂层的耐磨性,降低摩擦因数,疲劳磨损、粘附磨损及犁切现象明显减轻;当n-SiO2含量为1.5%(质量分数)时,复合涂层摩擦磨损性能最佳,试验条件下磨损量降低近4倍,摩擦因数降低23%,跑合期降低44%,复合涂层与GCr15钢环对磨时的磨损机制主要为疲劳磨损和轻微的粘附磨损。     

纳米SiO_2/GF/PA6复合材料力学性能和摩擦学性能研究

采用注塑成型法制备纳米SiO2和玻璃纤维混杂填充PA6尼龙复合材料,对PA6复合材料的力学性能和摩擦学性能进行实验研究,采用扫描电子显微镜观察分析磨损表面形貌及磨损机制。结果表明:纳米SiO2和玻璃纤维混杂填料能使PA6复合材料的拉伸强度和表面硬度增大,可以显著改善尼龙复合材料的摩擦学性能,以5%SiO2-20%GF材料的耐磨减摩性最好;纯PA6的磨损以黏着和犁削为主;当载荷较低时,复合材料的磨损机制主要表现为不同程度的磨粒磨损,但当载荷较高时,复合材料的磨损机制主要表现为不同程度的疲劳磨损。     

聚四氟乙烯与蒙脱土填充聚苯硫醚复合材料的摩擦磨损性能

通过模压成型制备出聚四氟乙烯(PTFE)乖蒙脱土填充的聚苯硫醚(PPS)复合材料,研究了PTFE与蒙脱土的单独和协同作用对PPS摩擦磨损性能的影响.结果表明:单独添加PTFE能够显著降低PPS的摩擦因数和磨损率,同时填充PTFE与蒙脱土可以进一步改善PPS的摩擦学性能;PPS 15%PTFE 5%蒙脱土复合材料的比磨损率最低,为0.69×10-6 mm3/Nm,其摩擦因数也最小,约为0.15.     

水润滑条件下聚丙烯/有机改性蒙脱土纳米复合材料摩擦磨损性能研究

针对2种有机改性蒙脱土(OMMT,TJ-2型和KH-V6型),研究了熔融插层法制备的聚丙烯(PP)/OMMT纳米复合材料在水润滑条件下的摩擦磨损性能,并用扫描电子显微镜观察分析了复合材料的磨损表面.结果表明:2种PP/OMMT纳米复合材料的摩擦因数和磨损率都随OMMT含量的增加先减小后增加.当TJ-2型OMMT质量分数为1.5%时,复合材料的摩擦因数和磨损率分别为纯PP的88%和48%;当KH-V6型OMMT质量分数为2%时,复合材料的摩擦因数和磨损率分别为纯PP的92%和50%.此外,在水介质中,随OMMT填充量的增加,PP/OMMT纳米复合材料的主要磨损形式依次是磨粒磨损、粘着磨损和磨粒磨损.     

纳米粒子和聚四氟乙烯填充UHMWPE复合材料的摩擦磨损性能研究

以纳米氧化锌(ZnO)和纳米蒙脱土(MMT)及聚四氟乙烯(PTFE)作为复合填料,通过热压成型工艺制备了纳米ZnO-MMT及PTFE填充超高分子量聚乙烯(UHMWPE)复合材料,采用销-盘式摩擦磨损试验机考察了纳米粒子对复合材料摩擦磨损性能的影响,用扫描电子显微镜观察了复合材料磨损表面形貌。结果表明当PTFE和MMT的填充量均保持为质量分数6%,填充纳米ZnO质量分数为4%~6%时的复合材料可获得较好的摩擦磨损性能,与不含纳米ZnO的复合材料相比,其摩擦因数最低下降了11.1%,而磨损率下降了83.3%。当复合填料中纳米ZnO含量较低时,复合材料的磨损机制主要表现为不同程度的粘着磨损,但当复合填料中纳米ZnO含量较高时,复合材料的磨损机制主要表现不同程度的粘着磨损和磨粒磨损,同时其复合材料的摩擦磨损性能出现了恶化现象。     

氧化物/尼龙1010复合材料滚动疲劳行为研究

以我国自主研制的尼龙1010为基体，氧化铁（Fe3O4）和氧化铜（CuO）为增强剂，进行氧化物／尼龙复合材料的滚动疲劳实验，研究氧化物／尼龙复合材料的滚动疲劳机制。通过实验发现周期性应力导致在材料临界深处形成显微裂纹和显微空穴成核，裂纹扩展导致形成片晶形磨屑，显微裂纹和显微空穴成核是剥层磨损的主要因素。氧化物颗粒割裂了尼龙1010的基体，在接触应力和摩擦热的复合作用下，表面金属氧化物颗粒由于复合材料表面界面疲劳开裂而剥落，形成表面疲劳。30％CuO／尼龙1010复合材料的抗滚动疲劳磨损性能最好，疲劳磨损量只有尼龙的70％左右；10％Fe3O4／尼龙1010复合材料耐磨性能最差，滚动疲劳磨损量是尼龙的2．4倍。     

Effects of SEBS-g-MA on tribological behaviour of nylon 66/organoclay nanocomposites

The tribological behaviour of nylon 66, nylon 66/organoclay nanocomposites and nylon 66/(SEBS-g-MA+organoclay) nanocomposites was studied by means of a pin-on-disk apparatus. The morphologies of the transfer films and the worn surfaces of specimens were observed with an optical microscope and a scanning electron microscopy (SEM). Wear of all of the specimens increases with increasing load; meanwhile the coefficient of friction almost linearly decreases. Wear of nylon 66/organoclay is larger than that of nylon 66. Adding SEBS-g-MA to the nylon 66/organoclay improves the wear resistance. The coefficient of friction of nylon 66/organoclay is slightly less than that of nylon 66 at various loads. The coefficient of friction of nylon 66/(SEBS-g-MA+organoclay) is the lowest at every load. If the transfer film is thin, uniform and continuous, the wear loss and the coefficient of friction are low.     

微米氧化铝/尼龙复合材料在不同条件下的滚滑摩擦磨损行为研究

以微米氧化铝(Al2O3)为增强剂,尼龙1010为基体,进行氧化铝/尼龙复合材料在干摩擦和水润滑条件下的滚滑动摩擦磨损实验。通过实验发现,水能降低氧化铝/尼龙复合材料的摩擦因数,但增大了磨损量。水润滑时,尼龙1010材料的摩擦因数为0.09,为干摩擦时的45%;氧化铝/尼龙复合材料的平均摩擦因数为0.1195,比尼龙增加了24.7%,是干摩擦时的42%。水润滑时尼龙1010的磨损量为干摩擦时的2.5倍,复合材料平均磨损量为干摩擦时2.8倍。     

Tribological Investigation of MC PA6 Reinforced by Boron Nitride of Single Layer

Monomer casting polyamide 6 (MC PA6)/boron nitride of single layer (SBN) nanocomposites were successfully synthesized by in situ ring-opening polymerization. SBN was prepared by sonication assisted with solution beforehand. Studies on frictional and wear performance of the nanocomposites were carried out on a block-on-ring tester. The results showed that the nanocomposites had lower wear rates and friction coefficients in comparison with neat MC PA6. The incorporation of 0.25 wt% SBN into MC PA6 significantly reduced wear and friction under dry sliding; however, with further increasing the SBN loading, both wear rate and friction coefficient began to increase. The SEM micrographs of the worn surface revealed their friction and wear mechanisms. Pure MCPA6 was characterized by severe lamellar spalling with adhesive wear being the major wear form which caused high friction and wear. The wear modes of the nanocomposites became mainly abrasive wear with lower content of SBN and displayed fatigue wear with higher content of SBN. The morphology of a uniform transfer film on the counterpart ring and fine wear debris for the nanocomposites corresponded to the improved tribological performance.     

聚合物填充聚四氟乙烯复合材料的摩擦磨损性能

采用机械共混-冷压成型-烧结的工艺制备了PEEK、PPS填充PTFE基粘弹．摩擦型阻尼材料，用环-块式磨损试验机研究了在干摩擦条件下的摩擦磨损性能；用扫描电子显微镜观察磨损表面形貌和内部组织结构。结果表明：混合填充PEEK和PPS时，2种填充物的比例对材料的摩擦因数影响不大，当二者含量相近时，摩擦因数最大；填充物对磨损性能的影响与对摩擦因数的相同；随着PEEK含量的增加和PPS含量的减少，材料的磨损方式由疲劳剥落磨损为主转变为犁削、粘着磨损；PTFE含量的增加，使得复合材料的摩擦因数减小，而磨损有所增大。综合考虑认为，PTFE与适当比例的PEEK／PPS混合填充，具有合适的摩擦因数和较好的耐磨性，能够满足特殊工况下阻尼材料的需要。     

Two-body free-abrasive wear of polyethylene, nylon1010, expoxy and polyurethane coatings

Two-body free-abrasive wear behavior of polyethylene (PE) coatings, nylon1010 (PA1010) coatings, polyurethane (PU) coatings, and expoxy (EP) coatings was investigated. Abrasive wear tests were performed on a turnplate abrasive wear test machine JMM. Hardened and low-temperature tempered steel 45 was used as a reference material. The results shown that in abrasive wear resistance, the PU coatings are approximately 120%, about 5 times larger than the PE coatings and 3 times larger than the PA1010 coatings and the EP coatings, the EP coatings and the PA1010 coatings approach to 40%, and the PE coatings about 20% compared with the reference material (steel 45). Of all the tested polymer coatings, the PU coatings are the best, the PE coatings the worst, and the PA1010 coatings and the EP coatings intermediate. Wear morphologies of the polymer coatings were observed by scanning electron microscope (SEM). Main wear mechanisms of the tested polymer coatings include ploughing wear for the PE coatings and the PA1010 coatings, fatigue wear for the PU coatings and fatigue fracture as well as some brittle fracture and somewhat ploughing wear for the EP coatings.     

油润滑下MoSi2材料的摩擦磨损性能

运用M-200型摩擦磨损试验机测定了油润滑条件下MoSi2与45调质钢、45淬火钢和CrWMn钢配对时的摩擦磨损性能，采用扫描电镜和微探针分析了摩擦副表面的形貌，探讨了磨损机理：结果表明：采用20号机械油润滑可有效地降低MoSi2材料的磨损率及摩擦因数；与低硬度的45调质钢和45淬火钢对摩时，MoSi2材料的主要磨损机制为晶间断裂、疲劳断裂、轻微粘着磨损和磨粒磨损；MoSi2材料与高硬度的CrWMn钢对摩时，主要磨损机制表现为粘着磨损、微犁削式磨粒磨损，并在偶件表面材料凸点的前端形成楔块。     

载流下MoS2/Ag纳米复合薄膜摩擦学性能

MoS₂基纳米复合薄膜具有良好的摩擦学性能,但较差的导电性能限制了其在载流条件下作为润滑材料的应用。为提高MoS₂基纳米复合薄膜的导电性能,采用非平衡磁控溅射系统沉积2种不同Ag含量的MoS₂/Ag纳米复合薄膜,并在不同的电流条件下研究MoS₂/Ag纳米复合薄膜与GCr15钢球对摩时的摩擦学性能。结果表明：在载流下2种MoS₂/Ag纳米复合薄膜表现出相似的摩擦性能,而低掺杂MoS₂/Ag薄膜具有更佳的耐磨性能,这归因于低掺杂MoS₂/Ag薄膜具有较好的力学性能;无载流时,MoS₂/Ag纳米复合薄膜在摩擦过程中生成的氧化物颗粒增加了磨损、降低了润滑性,磨损机制主要为磨粒磨损;电流小于0.5 A时,电流促进了转移膜形成,使得摩擦因数降低,但磨损率增加,磨损机制主要为黏着磨损;当电流大于0.5 A时,由于电弧烧蚀加速了薄膜的磨损,磨损机制主要为磨粒磨损、黏着磨损和电弧腐蚀磨损。     

二维层状Ni/β-Ni(OH)2纳米复合材料的制备及其摩擦学性能研究

采用水热反应制备出β-Ni(OH)2,然后通过水热还原得到Ni/β-Ni(OH)2纳米复合粉体材料,采用X射线衍射仪(XRD)和扫描电子显微镜(SEM)对复合材料的相结构、成分及形貌进行表征分析。采用四球摩擦磨损试验机评价制备的Ni/β-Ni(OH)2作为润滑油添加剂的摩擦学性能,基础油为PAO6。摩擦试验后,采用SEM分析典型试验钢球磨斑的表面形貌,利用能谱仪(EDS)研究磨斑表面化学元素的组成,探讨Ni/β-Ni(OH)2纳米复合润滑添加剂的减摩抗磨机制。结果表明:Ni/β-Ni(OH)2纳米复合材料作为润滑添加剂具有极好的减摩抗磨性能,显著优于基础油PAO6和未负载纳米Ni的二维β-Ni(OH)2层状材料;与基础油相比,添加0.1%质量分数Ni/β-Ni(OH)2添加剂的油样的摩擦因数和磨斑直径分别降低了17.6%和41.5%;Ni/β-Ni(OH)2纳米复合粉体综合了纳米Ni及层状β-Ni(OH)2两部分结构特性,在摩擦过程中,复合材料中的纳米金属粒子Ni与层状结构材料β-Ni(OH)2能够相互增强起到协同润滑作用。     

Fretting wear behaviors of steel wires under friction-increasing grease conditions

Fretting wear tests were performed on the self-made fretting wear rig to investigate fretting wear behaviors of steel wires under friction-increasing grease conditions. The results demonstrated that the fretting regimes were dependent on displacement amplitudes and normal loads. The friction coefficient exhibited different variation trends in different fretting regimes. Friction-increasing grease changed the fretting running behavior and had a very good wear resistance for steel wires. Wear was slight in partial slip regime. Mixed regime was characterized by plastic deformation, fatigue cracks and abrasive wear. Slip regime presented main damage mechanisms of abrasive wear, fatigue wear and oxidation.     

石墨填充聚四氟乙烯基复合材料的摩擦学性能

为了研制PTFE基粘弹-摩擦型阻尼材料,采用机械共混-冷压成型-烧结的工艺制备了石墨、聚苯硫醚、聚醚醚酮混合填充PTFE基复合材料,利用环-块式磨损试验机,在干摩擦条件下考察了复合材料的摩擦学性能,并用扫描电镜观察了磨损表面形貌,研究了复合材料的磨损机制。结果表明:PTFE含量不同的复合材料,随石墨填充量的增大,摩擦因数和磨损率的变化趋势不同,磨损主要由犁削、粘着和疲劳剥落中的一种或几种引起;适当配比的PTFE基复合材料具有较好的摩擦阻尼性能,能够满足粘弹-摩擦阻尼材料的要求。