纳米CaCO3、Cu混合物润滑油添加剂的摩擦学性能

采用纳米碳酸钙、纳米铜粒子混合物作为润滑油添加剂,利用四球摩擦磨损试验机考察了含纳米碳酸钙、纳米铜粒子添加剂的润滑油的摩擦学性能;用扫描电子显微镜（SEM）考察了磨痕表面的形貌;用原子力显微镜和扫描电子显微镜（SEM）观察分析了在磨损表面纳米粒子的形态与分布。研究结果表明,纳米碳酸钙、纳米铜的混合粒子的总添加量为0.6％,质量比为1：1时,润滑油具有最佳的摩擦学性能;润滑油中纳米碳酸钙、纳米铜混合物粒子添加剂的优良摩擦学性能与纳米粒子在表面存在形态相关。     

PA66/Si_3N_4纳米复合材料的摩擦磨损性能

采用双螺杆挤出机熔融共混和注射成型方法制备了PA66/Si3N4纳米复合材料.研究了纳米Si3N4添加量对复合材料的力学性能和摩擦磨损性能的影响.通过对试样磨损表面及其对摩副表面上转移膜的扫描电子显微镜(SEM)观察和X射线光电子能谱(XPS)分析,探讨了其磨损机制.结果表明,纳米Si3N4的加入降低了基体的拉伸强度和弯曲强度,但是在PA66中加入适量的纳米Si3N4颗粒后,摩擦过程中有利于生成较均匀的转移膜,从而降低摩擦因数.同时磨屑里的纳米Si3N4镶嵌到试样摩擦表面,使表面得到局部增强,从而提高其耐磨性能.     

纳米金属粉填充Ekonol/PTFE复合材料的摩擦磨损性能研究

评价了分别用不同体积含量的纳米镍粉和纳米铜粉填充聚苯酯/聚四氟乙烯(Ekonol/PTFE)复合材料体系的力学性能,利用M-200型磨损试验机研究了纳米Ni、纳米Cu含量对Ekonol/PTFE复合材料摩擦学性能的影响,借助扫描电子显微镜和能谱分析手段考察试样磨损表面和磨屑,并探讨其摩擦磨损机制。结果表明,纳米Ni能在一定范围内增加Ekonol/PTFE复合材料的冲击强度;纳米金属粉填入量较小时均能增加复合材料的洛氏硬度。纳米Ni与纳米Cu均能增加Ekonol/PTFE复合材料的摩擦因数并降低磨损率。其原因在于纳米金属粉在复合材料摩擦表面富集,通过金属分子间的吸引作用,增大复合材料的摩擦因数。     

纳米Fe3O4填充聚四氟乙烯摩擦磨损性能的研究.doc

利用机械共混、冷压成型和烧结工艺制备不同含量的磁性纳米Fe3O4填充聚四氟乙烯(PTFE)复合密封材料,采用MM 200型摩擦磨损试验机考察其在干摩擦下与45#钢对磨时的摩擦磨损性能,借助扫描电子显微镜（SEM）对磨损表面形貌进行观察并分析磨损机制。结果表明：随磁性纳米Fe3O4含量的增加,复合材料的硬度显著提高,摩擦因数呈现先增大后减小再增大的变化趋势,耐磨性能得到明显改善;当Fe3O4质量分数为15%时,复合密封材料的摩擦因数较小,体积磨损率与纯PTFE相比降低两个数量级;随着Fe3O4含量的增加,磨损机制由纯PTFE的黏着磨损转变为黏着磨损与磨粒磨损共同作用。     

聚甲醛多元耐磨复合材料的摩擦学特性

利用环块磨损试验机对模压法制备的Ekonol/G/MoS2/POM复合材料的摩擦学性能进行了测试,利用DSC、红外光谱（FTIR）分析方法对其磨屑进行了研究,用SEM方法对复合材料的磨损表面进行了观察和分析,进而对复合材料的磨损机理进行了探讨.结果表明：POM复合材料磨屑的熔点比相应模压材料有所降低,且磨屑的熔限比相应的模压材料有所加宽;随着Ekonol含量的增加,复合材料的摩擦因数和磨损量呈先减小后增大的趋势,其磨损机理发生了由犁沟、粘着磨损向疲劳磨损、磨粒磨损的转变。     

含纳米PTFE颗粒润滑脂的润滑性能研究

在四球摩擦磨损试验机上考察纳米PTFE颗粒作为添加剂对复合钛基润滑脂摩擦磨损性能的影响,采用扫描电子显微镜分析试验钢球磨斑的表面形貌,并利用X射线光电子能谱仪检测磨斑表面化学元素的组成及状态。结果表明,在一定添加量范围内,纳米PTFE可以改善复合钛基润滑脂的摩擦磨损性能,其中纳米PTFE质量分数为3%时,复合钛基润滑脂具有最佳的抗磨、减摩性能,可使摩擦因数、磨斑直径分别降低约25.4%和18.9%。纳米PTFE颗粒在钢球表面发生摩擦化学反应,生成了一层金属氟化物,有效地抑制了摩擦表面的黏着磨损和接触疲劳。     

纳米石墨/聚丙烯酸乙酯复合乳液的合成及其润滑性能研究

采用自由基乳液聚合方法合成了纳米石墨／聚丙烯酸乙酯复合乳液，并用四球摩擦磨损试验机对其润滑性能进行了评估。结果表明，一定浓度的纳米石墨／聚丙烯酸乙酯复合乳液可有效提高水基液的承载能力，降低磨损量。采用IRMM对摩擦磨损试验后的钢球磨斑表面进行分析，结果表明：磨痕变浅，磨斑减小，有效降低了磨损。     

TiN、CrN的环境摩擦磨损对比研究

采用直流叠加脉冲偏压电弧离子镀技术在45钢表面沉积了TiN、CrN薄膜。用显微硬度计测试了薄膜的硬度,用划痕仪测量了薄膜的膜基结合力,用球-盘式摩擦磨损试验机评价了不同介质条件下（干摩擦、水润滑、油润滑）TiN、CrN薄膜的摩擦学特性,用表面轮廓仪测试了薄膜磨痕处的磨损轮廓,用扫描电镜（SEM）观察了薄膜磨痕形貌。结果表明,相对于干摩擦条件下,在水润滑和油润滑条件下TiN和CrN薄膜的摩擦因数和磨痕深度都有所降低。在相同的介质条件下,CrN薄膜的摩擦因数和磨痕深度始终小于TiN薄膜。     

聚醚醚酮多元复合材料的摩擦学研究

采用模压法制备了PEEK多元复合材料,用环-块磨损实验机对复合材料进行了磨损试验,用SEM方法对复合材料的磨损表面进行了观察和分析,并利用DSC、红外光谱（FTIR）和SEM分析方法对复合材料的磨屑进行了研究,并探讨了复合材料的磨损机制。结果表明：与PEEK相比,复合材料具有优良的摩擦学性能;PEEK复合材料磨屑的熔点比相应模压材料有所降低,且磨屑的熔限比相应的模压材料有所加宽;随着Ekonol含量的增加,复合材料的磨损机制发生了由粘着磨损为主向疲劳磨损为主的转变;通过磨屑形貌分析和对磨损表面的观察与分析所得的关于复合材料的磨损机制的结论是一致的。     

氧化石墨烯和纳米SiO2增强PTFE复合材料的摩擦磨损行为

为研究具有层状结构和球状结构的纳米填料之间的相互作用对聚四氟乙烯（PTFE）复合材料摩擦磨损行为的影响,采用冷冻干燥超声共混-冷压-热烧结法制备纳米二氧化硅（nano-SiO2）和氧化石墨烯（GO）填充改性PTFE复合材料。利用LSM-2R往复式摩擦磨损试验机测试干摩擦条件下nano-SiO2和GO复配改性PTFE复合材料的摩擦学性能,采用MicroXAM-800非接触式三维表面轮廓仪、扫描电子显微镜(SEM)和能谱仪(EDS)分析表征转移膜形貌、元素分布和磨痕表面三维形貌,从微观层面揭示nano-SiO2和GO的减摩机制。结果表明：单独填充nano-SiO2与GO均可改善PTFE复合材料的摩擦学特性,其中在较低添加量下,GO在提高PTFE耐磨性方面明显优于nano-SiO2;GO和nano-SiO2复配填充时存在协同效应,与单一填充相比进一步改善了复合材料的摩擦学性能;相比于纯PTFE,3%nano-SiO2/0.5%GO/PTFE复合材料的磨损率降低60.36%。机制分析表明,协同作用和均匀连续转移膜的形成是nano-SiO2和GO增强PTFE复合材料性能优异的主要原因。     

纳米Al2O3对聚四氟乙烯工程材料性能的影响

用压制和烧结的方法，制备了纳米Al2O3和聚四氟乙烯（PTFE）的复合材料。研究了纳米Al2O3粒子对PTFE的摩擦、磨损、硬度、耐冲击强度等性能的影响。结果表明：纳米Al2O3粒子不仅显著地提高了PTFE耐磨性，而且降低了PTFE的摩擦系数，同时使PTFE的硬度增大。对作用机理进行分析和探讨，提出了“纳米粒子在摩擦磨损表面产生富积及重新嵌入“的观点，为材料的改性研究提供参考。     

Friction Properties of Poly(vinyl alcohol) Hydrogel: Effects of Degree of Polymerization and Saponification Value

In this study, the friction of eight kinds of poly(vinyl alcohol) hydrogel (PVA-H) samples has been studied under various load and velocity conditions to elucidate the effects of PVA factors such as the degree of polymerization (DP) and the saponification value (SV) on the tribological behavior of PVA-H. Results showed the variations of the friction properties due to the PVA factors in the two friction conditions found for the hydrogels: elastic friction and hydrodynamic lubrication. In the elastic friction, the larger frictions were induced by the higher values of DP and SV. In the hydrodynamic lubrication, on the other hand, PVA-Hs with lower SV showed larger friction. The results can then be used to adjust the parameters of PVA-H in order to get given friction properties, for instance for the friction between catheter or scalpel and PVA-H, which can be used as a biomodel material of artery or oral mucosa, for the training of surgeons.     

含纳米CuO锂基润滑脂摩擦学性能研究

为改善锂基润滑脂摩擦学性能,制备不同添加量纳米CuO改性的锂基润滑脂。采用3H-2000PS2比表面及微孔分析仪对纳米CuO粒子进行表征,采用四球摩擦磨损试验机分析纳米CuO添加量对锂基润滑脂摩擦学性能的影响,采用扫描电镜(SEM)和三维形貌分析仪分析试验后钢球磨痕形貌。结果表明:纳米CuO质量分数为0.60%时锂基润滑脂具有最佳的抗磨减摩效果,摩擦因数和磨斑直径较基础脂分别降低24%和12%;一定添加量下,纳米CuO对磨损表面具有修复作用,含质量分数0.60%纳米氧化铜的润滑脂润滑时,磨损表面具有较低的表面粗糙度和较少的犁沟,表现出最佳的抗磨性能。     

沉积气压对W-S-C复合薄膜结构和摩擦学性能的影响

采用磁控溅射方法制备W-S-C复合薄膜,研究沉积气压对薄膜结构和摩擦学性能的影响。结果表明,复合膜以非晶或纳米晶结构生长,沉积气压低时薄膜中C含量高,薄膜结构致密;沉积气压高时薄膜中WSx含量高,薄膜致密性下降。复合膜硬度在HV420～500之间,并且随着沉积气压的增加,硬度逐渐下降。在潮湿大气中的摩擦磨损实验表明,实验载荷越大摩擦因数越小;随着沉积气压的增加,复合膜的摩擦因数先降低后增加;当沉积气压在0.45～0.55 Pa时,复合膜的摩擦因数最低约为0.1,耐磨性能最好。     

不同维度碳纳米材料对水润滑橡胶轴承摩擦磨损性能的影响

以碳纳米管(MWNT)、多层石墨烯(MLG)和纳米石墨(NG)为填料,采用溶液共混法制备3种不同维度碳纳米材料改性的丁腈橡胶基复合材料试样。在水润滑及重载工况下对3种材料进行摩擦磨损试验,结合摩擦因数、表面形貌和磨损量等参数的测试对材料的摩擦学性能进行比较,通过SEM电镜表征,揭示不同维度碳纳米填料的作用机制。结果表明:碳纳米材料的加入能够明显降低丁腈橡胶材料低速下的摩擦因数,提高其抗磨性能,其中三维结构纳米石墨的改性效果最优。3种碳纳米填料的作用机制分别为:一维碳纳米管因长径比大,易与橡胶分子形成物理交联点,并且起到微轴承作用;二维石墨烯易于脱落转移形成良好的固体润滑膜来改善摩擦磨损性能;三维纳米石墨由于颗粒的粗糙表面与橡胶基体相互嵌入,能增加黏附力,且能减少界面脱黏现象。     

富勒烯与纳米二硫化钨极压抗磨协同性能研究

为探讨富勒烯与纳米二硫化钨的极压抗磨协同性能,利用四球试验机考察富勒烯与纳米二硫化钨复配后在PAO基础油中的摩擦学性能;采用扫描电子显微镜对试验钢球磨痕形貌进行分析,探究富勒烯与纳米二硫化钨的协同作用机制。结果表明:富勒烯与纳米二硫化钨单剂对PAO基础油减摩抗磨效果的改善不明显,而富勒烯与纳米二硫化钨复配后可明显提高油样的减摩抗磨性能,其中质量分数0.01%富勒烯与0.005%二硫化钨复配后减摩抗磨协同效果最优,这是因为富勒烯能够实现滚动摩擦,而纳米二硫化钨能够沉淀到磨损处,起到修复的作用,两者的协同作用,提高了基础油的抗磨减摩性能;富勒烯与纳米二硫化钨复配并不能提高基础油极压性能,这是因为富勒烯不能与纳米二硫化钨生成新的物质来提高基础油的承载能力。     

Carbon Nanotube Reinforced Polyimide Thin-film for High Wear Durability

In this paper, the influence of single walled carbon nano tubes (SWCNTs) addition on the tribological properties of the polyimide (PI) films on silicon substrate was studied. PI films, with and without SWCNTs, were spin coated onto the Si surface. Coefficient of friction and wear durability were characterized using a ball-on-disk tribometer by employing a 4 mm diameter Si₃N₄ ball sliding against the film, at a contact pressure of ∼370 MPa, and a sliding velocity of 0.042 ms⁻¹. Water contact angle, AFM topography, and nano-indentation tests were conducted to study the physical and mechanical properties of the films. SWCNTs marginally increased the water contact angle of PI film. The addition of SWCNTs to PI has increased the hardness and elastic modulus of pristine PI films by 60–70%. The coefficient of friction of PI films increased slightly (∼20%) after the addition of SWCNTs, whereas, there was at least two-fold increase in the wear life of the film based on the film failure condition of coefficient of friction higher than 0.3. However, the film did not show any sign of wear even after 100,000 cycles of rotation indicating its robustness. This increase in the wear durability due to the addition of the SWCNTs is believed to be because of the improvement in the load-bearing capacity of the composite film and sliding induced microstructural changes of the composite film.     

Tribological behaviors of Ti–6Al–4V modified by chemical methods

In order to improve the tribological properties of titanium-based implants, sodium hydroxide (NaOH), hydrogen peroxide (H₂O₂) solutions, sol–gel hydroxyapatite (HA) film, thermal treatment and combined methods of NaOH solution/HA film, H₂O₂ solution/HA film are used to modify the surfaces of Ti–6Al–4V (coded TC4). The chemical states of some typical elements in the modified surfaces were detected by means of X-ray photoelectron spectroscopy (XPS). The tribological properties of modified surfaces sliding against an AISI52100 steel ball were evaluated on a reciprocating friction and wear tester. As the results, complex surfaces with varied components are obtained. All the methods are effective in improving the wear resistance of Ti–6Al–4V in different degrees. Among all, the surface modified by the combined method of NaOH solution/HA film gives the best tribological performances. The friction coefficient is also greatly reduced by the modification of NaOH solution. The order of the wear resistance under 3 N is as following: Ti–NaOH–HA>Ti–NaOH>Ti–HA>Ti–H₂O₂–HA>Ti–H₂O₂ >Ti–500; under 1 N is Ti–HA, Ti–NaOH–HA>Ti–NaOH. For Ti–H₂O₂, a very low friction coefficient and long wear life over 2000 passes is obtained under 1 N. SEM observation of the morphologies of worn surfaces indicates that the wear of TC4 is characteristic of abrasive wear. Differently, abrasion, plastic deformation and micro–crack dominate the wear of Ti–HA; slight abrasive wear dominate the wear mechanism of Ti–NaOH and microfracture and abrasive wear for Ti–NaOH–HA and Ti–H₂O₂–HA, while the sample modified by thermal treatment is characterized by sever fracture. The superior friction reduction and wear resistance of HA films are greatly attributed to the slight plastic deformation of the film. NaOH solution is superior in improving the wear resistance and decreasing the friction coefficient under relative higher load (3 N) and H₂O₂ is helpful to reduce friction and wear under relatively lower load (1 N). Combined method of Ti–NaOH–HA is suggested to improve the wear resistance of Ti–6Al–4V for medial applications under fretting situations.     

离子液体对WS2纳米润滑油摩擦学性能的影响

纳米二硫化钨的润滑性能优异,但由于其在润滑油中易团聚沉降,影响了其在润滑油中抗磨减摩性能的发挥。为改善纳米WS2的抗磨减摩性能,将一种磷酸盐离子液体添加到WS2纳米润滑油中,通过四球摩擦试验机对其摩擦学性能进行测试,采用XPS、EDS和电子显微镜等表征方法对钢球磨损表面进行表征。结果表明：虽然添加离子液体后纳米润滑油的摩擦因数略微上升,但相对基础油,离子液体仍可使其摩擦因数最大降低28%,同时能显著地减小磨斑直径,最大降幅达到了44%。离子液体在摩擦过程中与WS2反应生成PW,该物质作为催化剂加速了摩擦过程中的氧化反应,生成的化合物作为化学摩擦膜减少磨损,提升润滑油抗磨减摩性能。     

纳米氧化镧和蛇纹石改性PTFE复合材料淡水环境摩擦学性能预测*

以聚四氟乙烯(PTFE)为基体,改性纳米氧化镧(nano-La_2O_3)、改性纳米蛇纹石(nano-serpentine)为添加剂,采用均匀设计法,制备nano-La_2O_3/nano-serpentine/PTFE复合材料。自制水环境模拟装置,设计并进行淡水环境复合材料摩擦学实验。使用Origin软件对实验数据进行曲线拟合,使用SPSS软件进行多元回归分析,得到摩擦学性能回归方程,通过MATLAB解出回归方程摩擦因数和磨损率理论最优解。以复合材料最优理论配比制作试件,进行摩擦学性能对比实验和磨损表面形貌分析。结果表明:复合材料摩擦学性能实验值与回归分析理论结果基本吻合,摩擦因数误差控制在5%以内,磨损率误差控制在10%以内,证明研究所用方法对复合材料摩擦学性能预测具有可行性。