羟基硅酸盐/纳米铜复合添加剂摩擦学性能研究

由羟基硅酸镁和纳米铜粉体按质量比1∶1组成复合添加剂,利用MJ-800型四球摩擦磨损试验机考察复合粉体、硅酸盐粉体和纳米铜分别作为N68基础油添加剂的摩擦学性能,借助JSM3010型扫描电子显微镜及EDS测试分析钢球磨痕的表面形貌和成分组成,研究了添加剂的作用机制.结果表明:添加剂的引入明显改善了基础油的摩擦学性能,添加剂粒子通过吸附、填充、微滚珠以及熔融铺展作用降低钢球磨损,并对磨损表面进行一定的修复;硅酸盐粉体和纳米铜表现出良好的协同抗磨效应,复合添加剂的极压抗磨性能优于硅酸盐粉体或纳米铜单独作为添加剂.     

油润滑条件下有机物修饰纳米铜颗粒改善铁基摩擦副摩擦磨损的研究

在球盘式摩擦磨损试验机上考察了有机物修饰的纳米铜颗粒作为50CC润滑油添加剂的摩擦学性能；采用SEM和EDS分析了磨损表面形貌和表面膜元素组成。探讨了纳米铜颗粒的摩擦学作用机制：结果表明：有机物修饰的纳米铜颗粒作为添加剂能显著改善50CC润滑油的抗磨减摩性能，含0．05％纳米铜油样润滑下的摩擦因数与磨损量同基础油润滑下相比分别降低了27．6％与60％。分析后认为，纳米铜颗粒通过对摩擦表面进行修复及在摩擦表面成膜两种作用有效地改善了摩擦磨损性能。     

表面修饰纳米铜粒子的制备及其摩擦学性能

以微乳化化学还原法制备出表面修饰纳米铜粒子,它们在基础油中显示出良好的油溶性,在苯、甲苯等有机溶剂中有良好的分散性和分散稳定性。用四球摩擦磨损试验机考察了其在26#白油中的摩擦学性能,并对其摩擦化学作用机制进行了研究。结果表明,表面修饰纳米铜添加剂具有良好的抗磨和承载能力。磨斑的表面分析表明,纳米铜添加剂在边界润滑下形成了一层厚度约为13nm含单质铜的沉积膜是其具有良好摩擦学性能的主要原因。     

坡缕石载铜复合纳米润滑添加剂的制备及摩擦学性能研究

使用化学还原法制备坡缕石载铜复合纳米颗粒,以铸铁HT200作为摩擦副,采用MMU-10G摩擦磨损试验机研究该纳米颗粒作为润滑添加剂的摩擦学行为,使用EPMA-1600电子探针、金相显微镜、Genesis能谱仪进行试样磨损面形貌观察和组成元素分析。实验结果表明:该纳米复合颗粒作为润滑添加剂具有优异的减摩效果和良好的抗磨性能,与基础油150N相比,平均摩擦因数下降66.2%,对应的摩擦副试件磨损失重减少80.9%,在试件表面生成由纳米坡缕石和纳米铜共同组成的自修复膜。     

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。     

六方氮化硼负载纳米铜润滑添加剂的制备及其摩擦学性能研究

采用水热吸附及热解还原制备六方氮化硼负载纳米铜复合润滑添加剂(Cu/h-BN),利用透射电镜(TEM)、X射线衍射仪(XRD)、热重分析仪(TGA)以及红外光谱仪(FT-IR)对样品进行表征。将纳米润滑添加剂分散到聚α-烯烃(PAO10)中,采用球盘摩擦试验考察其摩擦学性能。采用扫描电子显微镜(SEM)对典型的磨痕进行形貌分析,采用X射线光电子能谱技术(XPS)对沉积的润滑膜表面的化学成分和价态进行分析,探讨复合润滑添加剂在摩擦过程中的润滑机制。结果表明：相比于六方氮化硼分散的油样,复合润滑添加剂Cu/h-BN中氮化硼在摩擦界面的层间滑移以及纳米铜粒子在磨痕界面的修复作用,使得PAO10基础油表现出更为优异的摩擦学性能,摩擦因数和磨损率分别降低了15.4%和29.7%。复合润滑添加剂Cu/h-BN中Cu和h-BN能发挥各自的结构优势,加速固体润滑膜的形成,从而实现优异的摩擦学性能。     

蒙脱石和坡缕石纳米润滑油添加剂的摩擦学性能

将KH550偶联剂修饰的纳米蒙脱石和纳米坡缕石,分别按质量比3%添加到150N基础油中制备2种纳米润滑油分散体系,用激光粒度分析仪、TEM、IR表征纳米添加剂的分散稳定性,在MMU-10G摩擦磨损试验机上测试2种纳米润滑油对45#钢的减摩抗磨性能,用SEM和EDX等分析摩擦试样表面成分与形貌的变化及影响摩擦学性能的机制。结果表明:纳米蒙脱石平均粒径较小,在150N基础油中分散更稳定;2种纳米润滑油相比纯基础油润滑时的平均摩擦因数和磨损量均明显下降,其中纳米蒙脱石润滑油的抗磨减摩性能最好;2种纳米润滑油润滑时摩擦试样表面分别生成了含蒙脱石和坡缕石特征元素的自修复膜层,其中蒙脱石特征元素含量相对较高,说明纳米蒙脱石摩擦学性能更好。     

纳米陶瓷润滑油添加剂润滑机制研究

研究了纳米陶瓷润滑油添加剂的润滑机制.采用四球试验机考察了纳米陶瓷润滑油的抗磨性能和极压性能,利用NT场致发射扫描式电子显微镜、高分辨率扫描电子显微镜、X射线光电子能谱仪,观察了磨损表面的纳米粒子形貌,分析了磨损表面的形貌及表面元素成分.结果表明,纳米陶瓷润滑油润滑时,摩擦表面的磨斑很光滑,磨斑表面有Si3N4存在;纳米陶瓷添加剂具有很好的抗磨和极压性能;纳米陶瓷粒子具有"滚珠效应".     

1,3-丙二胺改性纳米金刚石在润滑油中的摩擦学行为

激光粒度和TEM分析表明,经1,3-丙二胺改性的纳米金刚石的分散性得到显著改善.用MMW-1型立式万能摩擦磨损试验机考察了该改性纳米金刚石作为新型油基极压润滑添加剂的摩擦学行为,结果表明,改性纳米金刚石能明显改善摩擦副的微观磨损状态,显著增强基础油的抗磨性能,基础油中纳米金刚石质量分数为0.6%时,其极压值可提高42%,摩擦因数降低19.0%,磨斑直径降低15.4%,且磨斑较难分辨.     

不同组分比的坡缕石-铜复合纳米颗粒的摩擦学性能研究

将制备的不同组分比的坡缕石/铜复合纳米材料作为润滑添加剂在MMU-10G摩擦磨损试验机上测试其摩擦学性能,使用XJL-03倒置式金相显微镜和Genesis能谱仪对测试铸铁试样的磨损表面进行形貌观察和元素分析。结果表明:不同组分比的坡缕石铜润滑添加剂都具有一定的减摩抗磨效果,与基础油相比,摩擦因数最多下降了72.2%,试件磨损失重最多减少了90.6%;对磨试件的磨损失重量随着复合材料中铜组分的增加呈直线下降;而摩擦因数先随着铜组分的增加而缓慢上升,后急剧增大。     

Effect of Ag nanoparticles additive on the tribological behavior of multialkylated cyclopentanes (MACs)

Monodisperse Ag nanoparticles with a particle size of about 6–7 nm and low volatile multialkylated cyclopentanes (MACs) lubricant were prepared. The effect of Ag nanoparticles as additive in MACs base oil on the friction and wear behavior of MACs was investigated. The friction and wear test of a steel disc sliding against the same steel counterpart ball was carried out on an Optimal SRV oscillating friction and wear tester. The morphology and elemental distribution of the worn surface of both the steel ball and steel disc and the chemical feature of typical element thereof were examined using a JEM-1200EX scanning electron microscope (SEM) equipped with a Kevex energy dispersive X-ray analyzer attachment (EDS) and X-ray photoelectron spectroscope (XPS), respectively. Friction and wear test indicates that the wear resistance and load-carrying capacity of MACs base oil were markedly raised and its friction coefficient changed little when 2% Ag nanoparticles were added in it. Results of SEM/EDS and XPS show that Ag nanoparticles were deposited on the friction pair surfaces to form low shearing stress metal Ag protective film in rubbing process.     

二硫化钨发动机油的摩擦学性能研究

采用矿物油和合成油调配成半合成发动机油基础油,同时,通过表面化学修饰和吸附修饰表面改性超细二硫化钨颗粒,使其作为固体润滑添加剂稳定悬浮于基础油中,并加入一定量的功能添加剂,研制了一种二硫化钨发动机油。与国内外品牌发动机油进行摩擦学性能对比实验,发现该种发动机油的油膜强度分别是壳牌超凡喜力发动机油和国产长城发动机油的1.06倍和1.38倍,烧结载荷分别是它们的1.75倍和2.33倍,并且在392N、1450r/min、30min下长时间作用时,摩擦副的摩擦因数随时间的增长而减少,磨斑直径小,磨斑表面光滑,没有明显的犁沟出现。实验表明二硫化钨发动机油具有比国内外品牌发动机油更加优良的抗磨、减摩和极压性能。     

复合纳米润滑油添加剂的制备及其摩擦学性能

采用超声机械法制备了经过化学修饰的纳米Al2O3、SiO2、MgO复合粉体,使其稳定地分散在基础油中,考察了油的摩擦学性能,用扫描电镜(SEM)、X射线能量色谱仪(EDS)分析了摩擦副表面的形貌和组成,同时初步分析了添加剂的润滑机理.结果表明:所制备的复合纳米粉体为平均粒径58 nm的球形微粒,在润滑油中具有较好的抗磨减摩能力,表现出良好的自修复效果.     

纳米Al/Sn金属颗粒对润滑油抗磨极压性能的影响

利用四球试验机分别对添加有纳米铅粉、锡粉以及Al Sn金属粉的润滑油进行极压和抗磨性能实验。采用SEM(扫描电子显微镜)对摩擦表面进行观察，采用EDS(能量色散谱仪)对表面进行元素测定。测试结果表明．纳米Al Sn金属粉可在较宽的载荷范围内明显改善润滑油的极压抗磨性能。其作用机理是锡粉在低载荷阶段沉积到摩擦表面起到抗磨剂作用，铝粉在高载荷阶段沉积到摩擦表面起到极压剂作用．从而实现了在低载荷到高载荷范围内对润滑油抗磨极压性能的提高．     

硅酸盐粉体作为润滑油添加剂在金属磨损表面成膜机制

在润滑油中添加蛇纹石硅酸盐粉体,采用MM-200摩擦磨损试验机研究了45#钢-45#钢摩擦副磨损表面的自修复陶瓷膜层形成机制,借助SEM及EDAX测试分析自修复陶瓷膜层的表面形貌及表面成分组成。结果表明摩擦能量对硅酸盐添加剂在磨损表面形成自修复膜层有很大的影响:自修复膜层为氧化物陶瓷材料,主要成分来自于硅酸盐添加剂。在低载荷300 N时,摩擦因数减小,硅酸盐添加剂不能转移到磨损表面,不能形成自修复膜层,仅仅起到减磨作用。下试样的失重随磨损时间增加而增加;在试验时间为20 h时,试样失重达到最大值,随后试样的失重反而减小。在载荷为600 N、900 N,试验时间30 h摩擦磨损后,在金属表面形成自修复保护膜,磨损表面比较平整光滑,无明显的片层剥落和犁沟,摩擦发生在自修复陶瓷材料之间,摩擦因数增加。硅酸盐添加剂在机械剪切作用下变形,在金属的磨损表面上铺展,并且在摩擦磨损过程中不断向摩擦表面转移,形成了均匀光滑的自修复膜层。自修复膜层隔离了金属摩擦表面的直接接触,摩擦磨损发生在自修复膜层之间,有效地降低了金属的磨损。     

Tribological Effects of Vegetable Oil as Alternative Lubricant: A Pin-on-Disk Tribometer and Wear Study

The investigation of lubricated friction and wear is an extended study. The aim of this study is to investigate the friction and wear characteristics of double fractionated palm oil (DFPO) as a biolubricant using a pin-on-disk tribotester under loads of 50 and 100 N with rotating speeds of 1, 2, 3, 4, and 5 ms^?1 in a 1-h operation time. In this study, hydraulic oil and engine oil (SAE 40) were used as reference base lubricants. The experiment was conducted using aluminum pins and an SKD 11(alloy tool steel) disc lubricated with test lubricants. To investigate the wear and friction behavior, images of the worn surface were taken by optical microscopy. From the experimental results, the coefficient of friction (COF) rose when the sliding speed and load were high. In addition, the wear rate for a load of 100 N for all lubricants was almost always higher compared to lubricant with a load of 50 N. The results of this experiment reveal that the palm oil lubricant can be used as a lubricating oil, which would help to reduce the global demand for petroleum-based lubricants substantially.     

Study of the Regenerated Layer on the Worn Surface of a Cylinder Liner Lubricated by a Novel Silicate Additive in Lubricating Oil

Some special silicate particles as additives in lubricating oil have shown a certain self-repairing function for the rubbing pairs of industrial equipment in recent R&D of extreme pressure antiwear additives. This article introduces an investigation on the regenerated layer on the worn surface of a practical cylinder liner lubricated by lubricating oil with a silicate additive using some advanced techniques like transmission electron microscopy (TEM), atomic force microscopy (AFM), nano-hardness tester, scanning electron microscopy (SEM), auger electron spectroscopy (AES), and Raman spectroscopy. The basic formula of the mineral in the silicate additive is Al₄[Si₄O₁₀](OH)₄. Through some macro- and microanalyses, it was found that the silicate additive showed an obvious improving effect on their friction surface and self-repairing function. The roughness of the worn surface could be decreased greatly to several tens of nanometers, and its hardness was still above 10 GPa. The worn surface with some pits and cracks had been covered by a transparent regenerated layer, and the wear of cylinder liners was maintained at almost zero-wear level on average. The mechanism of the self-repairing function was approached. It was revealed that the silicate additive was acting as a catalyst to promote a series of complex tribochemical reactions to form a regenerated layer with amorphous carbon structure on the worn surface under high-friction temperature and pressure in the friction and wear process.     

冠醚化合物对钢/铜和钢/铝摩擦副的抗磨减摩性能研究

本文利用ＳＲＶ摩擦磨损试验机研究了省代苯并－１５－冠醚对钢／铜、钢／铝摩擦副的摩擦磨损性能的影响。结果表明,溴代苯并－１５－冠－５冠醚对钢／铜摩擦副起到减摩抗磨作用,对钢／铝摩擦副起到加速腐蚀磨损的作用。利用ＸＰＳ对磨痕表面进行了分析,发现铜和铝磨痕上发现了Ｂｒ,金属溴化物的生成减少了铜的摩擦和磨损,但却由于腐蚀而加速了铝合金的磨损。     

Tribochemical Behavior of Ashless Dialkyl Dithiophosphate Ester as an EP/AW Additive in Mineral Oil for Steel–Aluminum Contact

Dialkyl dithiophosphate ester (DDPE) used as an extreme pressure/antiwear (EP/AW) additive in mineral base oil (BO) was introduced to a steel–aluminum contact in this study. The tribological performance of DDPE was explored by means of a universal tribotester under different loads and durations. The worn aluminum surface topographies were observed and photographed via laser scanning confocal microscopy (LSCM) and scanning electron microscopy (SEM). Tribochemical interactions between the additive and aluminum surface were investigated using energy-dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). The distinction of chemical structure between lubricant untapped and the counterpart retrieved after a 3-h sliding process was detected by Fourier transform infrared spectroscopy (FTIR). The friction coefficient of a BO + DDPE-lubricated friction pair under 300 N shows the lowest value. LSCM and SEM images show that the aluminum surface lubricated with BO + DDPE was well protected under a high loading condition of 300 N, and the 3-h sliding process deteriorated the surface topography. However, DDPE was not able to offer an effective lubricating film under a mild condition of 50 N. EDS results of S and P elements on the worn surface indicate that a tribochemical film was generated under 300 N in the sliding process. XPS results further show that the chemical compounds in the tribochemical film included Al₂S₃, Al₂(SO₄)₃, AlPO₄, and Al₂O₃. The P-containing compound in the tribofilm acted as a sacrificial layer, whereas the S-containing compounds were more durable. FTIR analyses demonstrate that the phosphorus–sulfur double bond was broken up due to the tribochemical interactions.