PTFE/金属自润滑复合材料的磨损性能研究

用MM-200磨损试验机对纯PTFE板料、3层复合材料(DU)及钉板型复合材料的工作层在干摩擦定载荷条件下的磨损性能进行了研究;用SEM对磨损试样表面和磨屑形貌进行观察和分析.结果表明:铜和PTFE的复合能提高PTFE的耐磨性并改变其磨屑的形成机理;铜钉板取代传统的平钢板,不仅提高了材料的承载能力,也大大提高了材料的耐磨性能;在干摩擦条件下,纯PTFE板料主要发生粘着磨损和微凸体刨切,3层复合材料主要是磨粒磨损,钉板型复合材料的磨损机理是粘着磨损和磨粒磨损共同作用.     

聚醚醚酮及其复合材料的摩擦学研究进展

评述了聚醚醚酮（PEEK）及其复合材料的摩擦磨损性能，在滑动过程中形成的摩擦转移膜以及磨屑的研究，总结了聚合物基复合材料摩擦学研究的一般方法及规律，介绍了关于用PEEK复合材料制造的轴承，齿轮等进行的摩擦学研究，以及等离子体表面处理和颗粒增强对PEEK及其复合材料摩擦学性能的影响。     

聚苯酯/石墨/聚甲醛复合材料的制备及摩擦学性能

为了改善聚甲醛的摩擦学性能，用模压方法制备了聚苯酯／石墨／聚甲醛(Ekonol／G／POM)复合材料，通过摩擦磨损实验方法对材料的摩擦学性能进行了研究，并用SEM对磨损表面进行了观察和分析，在此基础上探讨了复合材料的磨损机理。结果表明：用模压法制备Ekonol／G／POM复合材料是可行的；适量加入Ekonol能改善POM的摩擦磨损性能，得到自润滑性能优良的Ekonol／G／POM复合材料；Ekonol加入量的多少，直接影响着复合材料的磨损机理，随着其含量的增加。磨损机理发生由粘着磨损到疲劳磨损的转变。     

TiCp/Ti6Al4V复合材料的耐磨性及磨损机制

为表征颗粒增强钛基复合材料在恶劣的磨粒磨损条件下的磨损行为,对熔铸法制备的TiCP/Ti6Al4V进行了磨粒磨损条件下的耐磨性试验,并利用SEM、EDX等技术分析了复合材料的磨损过程及磨损机制.研究表明:TiCP/Ti6Al4V复合材料的抗磨粒磨损性能,总体上随TiC颗粒体积分数的增加而提高,载荷越大、磨损时间越长,复合材料越容易表现出优异的耐磨性能;TiC的形态影响着耐磨性的提高,细小颗粒状或羽毛状TiC单位体积增加对耐磨性的贡献,比枝晶状TiC单位体积增加对耐磨性的贡献大约3.5倍;复合材料在磨损初始阶段,其磨损机制以形成犁削和磨沟为主,形成一次磨屑,随着增强相含量的提高,一次磨屑逐步减少,磨损以犁沟和剥层磨损为主,需要磨粒的反复作用才能形成磨屑,因此,耐磨性得到提高.     

剑麻纤维/酚醛树脂原位复合材料耐磨性能研究

为了探讨剑麻纤维对复合材料耐磨性能的影响,采用聚合填充工艺,通过模压成型方式制成剑麻纤维/酚醛树脂(SF/PF)原位复合材料.考察了SF的表面处理方式、用量、长度以及同玻璃纤维(GF)混杂增强与复合材料耐磨性能的关系;用扫描电镜(SEM)对材料磨损的表面形态结构进行了研究.结果表明,SF的用量和长度对材料的耐磨性能有一定影响,合适的用量和长度是得到高耐磨性能复合材料的必要条件,GF与SF混杂后材料的耐磨损性能随着SF用量的增加而增加;SEM揭示了复合材料相应的磨损机理.SF表面处理后复合材料的耐磨性能得到了显著提高.     

SiC颗粒增强PEEK树脂基复合材料的制备与性能EI

以纯PEEK粉,粒径为10μm的SiC粉为原料,在360℃热压制备了纯PEEK树脂和SiC体积比分别为10%,20%及30%的SiC/PEEK复合材料,并测试了材料的硬度、压缩性能、冲击性能以及摩擦磨损性能,用扫描电镜(SEM)观察了复合材料的断口以及磨损表面.实验结果表明:随着SiC添加量的增加复合材料的相对密度和硬度同时下降;SiC/PEEK复合材料的强度以及韧度随着SiC颗粒添加量的增加逐渐提高,当SiC达到某一含量时可以获得最佳的综合力学性能,此后随着SiC含量的进一步增多,复合材料的脆性增大,强度急剧下降;SiC/PEEK复合材料的摩擦系数随SiC的添加先增大后减小,磨损率逐渐变大,磨损机制由粘着磨损转向粘着磨损与犁削磨损共存最后变成全部的犁削磨损.     

玻璃纤维增强聚醚醚酮复合材料在水润滑下的摩擦学性能

利用球盘式摩擦磨损试验机考察了玻璃纤维(GF)增强聚醚醚酮(PEEK)复合材料在干摩擦和水润滑条件下的摩擦磨损性能,并探讨了其磨损机理。结果表明:在干摩擦和水润滑条件下,PEEK和GF/PEEK的摩擦因数和磨损率均随载荷和对磨时间的增加逐渐增大并趋于稳定,GF的加入可以显著降低GF/PEEK复合材料的摩擦因数和磨损率;在水润滑条件下,PEEK和GF/PEEK的摩擦因数和磨损率比干摩擦下显著降低。干摩擦下,PEEK以黏着磨损和磨粒磨损的混合磨损形式为主,水润滑条件下,磨损方式主要是以轻微的黏着磨损为主;干摩擦下,GF/PEEK磨损表面有大量的微观断裂裂纹和破碎,以磨粒磨损和疲劳磨损为主,水润滑条件下,磨损表面仅有微观切削的痕迹,磨损方式以轻微磨粒磨损为主。由于水的冷却和润滑作用,使得复合材料向对偶钢球的黏着转移明显减弱,同时阻止了对偶钢球上的Fe向复合材料磨损表面转移,从而减轻摩擦、降低摩擦表面温升,显著改善复合材料的摩擦磨损性能。     

SiC颗粒增强PEEK树脂基复合材料的制备与性能

以纯PEEK粉,粒径为10μm的SiC粉为原料,在360℃热压制备了纯PEEK树脂和SiC体积比分别为10%,20%及30%的SiC/PEEK复合材料,并测试了材料的硬度、压缩性能、冲击性能以及摩擦磨损性能,用扫描电镜(SEM)观察了复合材料的断口以及磨损表面.实验结果表明:随着SiC添加量的增加复合材料的相对密度和硬度同时下降;SiC/PEEK复合材料的强度以及韧度随着SiC颗粒添加量的增加逐渐提高,当SiC达到某一含量时可以获得最佳的综合力学性能,此后随着SiC含量的进一步增多,复合材料的脆性增大,强度急剧下降;SiC/PEEK复合材料的摩擦系数随SiC的添加先增大后减小,磨损率逐渐变大,磨损机制由粘着磨损转向粘着磨损与犁削磨损共存最后变成全部的犁削磨损.     

三维编织碳/环氧复合材料的摩擦磨损性能研究

采用RTM工艺制备了不同纤维体积比的三维编织碳／环氧（C3D／EP）复合材料。采用MM－200摩擦磨损试验机对其摩擦磨损特性进行了研究,并对C3D／EP复合材料的磨损机理进行了分析。结果表明,纤维体积比载荷和滑动速度对复合材料的摩擦系数和磨痕宽度均有明显的影响;C3D／EP复合材料的磨损机理主要为疲劳磨损和粘着磨损,当载荷或速度较小时,以疲劳磨损为主,反之则以粘着磨损为主。     

聚醚醚酮摩擦磨损行为和机理的研究

本工作通过摩擦过程中聚醚醚酮(PEEK)结构(包括材料与磨屑结构)的变化研究了PEEK的摩擦磨损机理。结果表明,低负载下,材料的摩擦表面不熔融,但表层的凝聚态结构发生了变化,摩擦状态不变,磨损是由于摩擦对偶的连续作用下产生疲劳而脱落。高负载下,材料表面熔融并发生氧化交联,摩擦状态改变,材料外形结构与内层凝集态结构发生变化,磨损是熔融了的表面层粘附于对偶上经进一步的交联反应后,受剪切力作用而脱落。材料在摩擦磨损过程中的表面状态决定了其摩擦磨损机理,并导致了材料摩擦磨损行为对负载的特殊依赖性。     

Effect of the SiC particle size on the dry sliding wear behavior of SiC and SiC–Gr-reinforced Al6061 composites

The effect of size of silicon carbide particles on the dry sliding wear properties of composites with three different sized SiC particles (19, 93, and 146 μm) has been studied. Wear behavior of Al6061/10 vol% SiC and Al6061/10 vol% SiC/5 vol% graphite composites processed by in situ powder metallurgy technique has been investigated using a pin-on-disk wear tester. The debris and wear surfaces of samples were identified using SEM. It was found that the porosity content and hardness of Al/10SiC composites decreased by 5 vol% graphite addition. The increased SiC particle size reduced the porosity, hardness, volume loss, and coefficient of friction of both types of composites. Moreover, the hybrid composites exhibited lower coefficient of friction and wear rates. The wear mechanism changed from mostly adhesive and micro-cutting in the Al/10SiC composite containing fine SiC particles to the prominently abrasive and delamination wear by increasing of SiC particle size. While the main wear mechanism for the unreinforced alloy was adhesive wear, all the hybrid composites were worn mainly by abrasion and delamination mechanisms.     

纳米SiC和微米SiC填充聚醚醚酮的磨损机理研究

利用热压法分别以纳米ＳｉＣ和微米ＳｉＣ作为填产制取了两类不同ＳｉＣ填充的聚醚醚酮复合材料，并对它们在干摩擦条件下的摩擦磨损性能进行了研究，同时还用扫描电子显微镜对摩擦表面形貌进行了观察，进而对材料的磨损机理作了分析与讨论。研究结果表明，１０％（ｗｔ）纳米ＳｉＣ作为填料能有效的改善其填充聚醚醚酮的摩擦磨损性能，而相同含量的微米ＳｉＣ作为填为只能使其填充聚醚醚酮的耐磨性能有所改善，但没有减摩效果。微米     

Surface Damage Characteristics and Specific Wear Rates of a New Continuous Carbon Fiber (CF) / Polyetheretherketone (PEEK) Composite under Sliding and Rolling Contact Conditions

The surface damage characteristics of a continuous carbon fiber reinforced composite, having a polyetheretherketone (PEEK) matrix, were investigated under sliding and rolling contact. The corresponding mechanisms were studied by the use of scanning electron microscopy (SEM) in three different fiber orientations, namely: Paralllel direction to the fibers, AntiParallel direction to the fibers, and Normal direction to the fibers. All wear tests were conducted against smooth steel surfaces for both contact conditions. Mechanical properties under tension, compression, and shear were investigated for the material at two different temperature levels, i.e. room temperature and 150 °C. The composite material under normal fiber orientation has the lowest specific wear rate in case of rolling wear while the parallel orientation has the lowest specific wear rate under sliding wear conditions. Both results were compared to wear data of the neat PEEK matrix.     

纳米ZrO2填充PEEK的摩擦表面和转移膜

研究了微粒直径分别为１０ｎｍ和８６ｎｍ的两种纳米ＺｒＯ２「填料含量为７．５％（质量分数,下同」填充ＰＥＥＫ的摩擦磨损性能,用扫描电子显微对摩擦表面和转移的形貌进行了观察研究,并对材料的磨损机理作了分析与讨论。     

High performance nanocomposites for tribological applications: Preparation and characterization

High performance nanocomposites were prepared by incorporating 0–12 vol.% nano-sized (39 nm) Al₂O₃ particles into PEEK matrix using compression molding. The microhardness and dynamic mechanical properties of the nanocomposites increase with increasing Al₂O₃ content. The wear resistance of the nanocomposites evaluated at a sliding speed of 1.0 m/s and nominal pressure from 0.5 MPa to 1.25 MPa under dry sliding conditions was improved more than threefold at 0.8 vol.% Al₂O₃ content. However, the wear resistance of the nanocomposites containing above 1.67 vol.% Al₂O₃ was deteriorated, despite their higher hardness and stiffness as compared to that of nanocomposites containing lower Al₂O₃ content. The surface roughness of the wear track formed over the countersurface increases with increasing Al₂O₃ content. The coefficient of friction of nanocomposites was higher than that of pure PEEK. SEM and optical microscopy have shown that wear of pure PEEK occurs by the mechanism of adhesion mainly, whereas of nanocomposites by microploughing and abrasion. Energy dispersive spectrometry (EDS) shows that Fe and alloying elements of countersurface transfer to the wear debris at higher Al₂O₃ content.     

Effects of potassium titanate whiskers and carbon fibers on the wear behavior of polyetheretherketone composite under water lubricated condition

The tribological behaviors of polyetheretherketone (PEEK) composite reinforced by carbon fiber (CF) and potassium titanate whiskers (PTW) have been investigated using the pin-on-disk configuration at different applied loads under water lubricated condition. The effects of micrometer carbon fiber and sub-micrometer PTW on the wear properties of the hybrid composite have been discussed. It was found that the PEEK/PTW/CF composite showed excellent tribological performance in water condition. High wear resistance and low friction coefficient were achieved under a wide range of loads. It was revealed that the two fillers worked synergetically to enhance the wear resistance of the hybrid reinforced PEEK composite. The carbon fiber carried the main load between the contact surfaces and protected the matrix from further severe abrasion of the counterpart. At the same time, the exposed PTW out of the polymer matrix around the fiber inhibited the direct scraping between the fiber edge and counterpart tip in some degree, so that the fibers could be less directly impacted during the subsequent sliding process and they were protected from severe damage. In addition, the reinforcement effect of PTW on PEEK could reduce the stress concentration on the carbon fiber-matrix interface, and thereby reduce the CF failure/damage. The reinforcement effect of PTW on PEEK might also restrict the crack initiation and propagation on the surface and subsurface of the composite, and therefore to protect the matrix from fatigue failure during the sliding process.