共查询到19条相似文献,搜索用时 109 毫秒
1.
2.
3.
《材料导报》2020,(5)
高温固体自润滑涂层能够在高温环境为摩擦副界面提供高性能的固体润滑膜,解决了高温环境下传统润滑油脂失效的问题,确保摩擦副在高温环境中可靠工作,并降低了能量损耗,近年来成为摩擦学领域研究的热点问题之一,并得到了快速发展。但是,在30~400℃时,诸多高温固体自润滑剂的减摩性能弱,摩擦系数较高。因此,国内外该领域科学家期望获得在30~1 000℃范围内摩擦学系数低、性能良好的高性能复合型固体自润滑涂层,其主要由基础相、润滑相和增强相组成,且它们的共同作用提供涂层在高温环境下的润滑能力。最近的研究显示,金属三元氧化物基高温自润滑涂层——主要以过渡族金属三元氧化物为基础相,由含有Magnéli同源相的二元和三元氧化物润滑材料发展而来的新型高温固体自润滑材料,逐渐成为解决高温域自润滑问题的首选材料。对此,围绕高温固体自润滑涂层的工程应用,发现其面临三个方面的挑战:(1)高性能复合固体自润滑涂层的体系设计;(2)适应复杂结构的可靠制备工艺;(3)服役期间的寿命可靠性评估。针对以上三个方面的问题,本文从高温自润滑涂层的设计体系、制备工艺发展、可靠性评估三个层面进行了综述,期望为高可靠性高温自润滑涂层的制备提供技术支持。首先是在设计体系方面,发现高温固体自润滑涂层不但要满足传统固体自润滑涂层包含基础相、润滑相和增强相及其共同作用提供自润滑的要求,还要满足高温环境的特殊要求。其次,科学家们期望获得制备高性能高温固体自润滑涂层的可靠工艺,但是均受到了工艺简便性与适应能力以及高温零部件结构表面复杂度等问题的限制,从而难以实现工程化。根据高温自润滑涂层的设计要求,在梳理介绍高温固体自润滑涂层的工艺中,发现高压高超音速喷涂技术在此领域具有一定的技术便捷性,可实现高温固体自润滑涂层的工程化。再次,分析梳理了高温自润滑涂层在服役周期内的寿命可靠性评估进展。研究发现,高温固体自润滑涂层的服役寿命逐渐从实验统计分析、应力与涂层结构之间的关联影响,向结合涂层微观界面与宏观性能的跨尺度结合的数值分析发展,这将为高可靠性高温固体自润滑涂层的制备和服役寿命评估信息化提供技术支持。 相似文献
4.
5.
6.
聚酰胺-酰亚胺树脂自润滑复合涂料的研制及性能 总被引:1,自引:0,他引:1
聚酰胺-酰亚胺树脂(PAI)具有优异的耐磨性能和粘结性能,以PAI为基体,添加固体润滑剂MoS2和聚四氟乙烯PTFE、BYK-163型分散剂、EFKA-3772型流平剂,制备了一种耐磨、耐蚀的PAI自润滑复合涂料。利用MRH-3G摩擦磨损试验机研究了不同固体润滑剂用量对涂层摩擦磨损性能的影响,采用金相显微镜和扫描电镜(SEM)观察涂层摩擦磨损前后的表面形貌。结果表明:当PAI自润滑复合涂料中MoS2含量为30%(质量分数)、PTFE含量为6%(质量分数)时,以其制备的PAI自润滑复合涂层致密性强,孔隙率少,耐腐蚀性强,摩擦磨损性能最佳,涂层其余理化性能也最佳。 相似文献
7.
采用端面带孔电极,在孔中填充MoS2,利用电火花沉积(ESD)方法在高速钢基体上制备Cu-MoS2自润滑涂层。分析自润滑涂层的成分及微观形貌,研究电容、沉积时间对自润滑涂层厚度的影响,以及自润滑涂层的摩擦性能和磨损机理。结果表明:采用这种电极制备的自润滑涂层中只存在MoS2和Cu。其微观形貌显示,自润滑涂层表面凹凸不平,并存在气孔,呈现典型的电火花沉积特征;在第3挡电容下,自润滑涂层的表面质量最好。随着电容、沉积时间的增加,涂层厚度出现先增加后下降的规律。在第3挡下制备的自润滑涂层的摩擦因数最小,随着摩擦时间的增加,在第1挡和第3挡下制备的自润滑涂层的摩擦因数都比较稳定,而在第5挡下制备的自润滑涂层的摩擦因数具有明显的上升趋势。SEM照片表明,磨损表面具有滑移剪切的现象。 相似文献
8.
摩擦磨损大多数情况下不利于机械设备,我国作为机械制造大国,降低摩擦磨损对工业进步及可持续发展有重大意义。陶瓷基高温自润滑复合涂层作为工业应用中常见体系之一,主要以硬质陶瓷为基体,并掺杂润滑材料作为第二相组成,使其一方面继承陶瓷相优异的高温稳定性及强度,另一方面提高在常见摩擦环境下的润滑性能,因此被广泛应用于船舶、航空航天、生物科技、高速列车等领域,受到研究人员的广泛关注与探索。本文以陶瓷基高温自润滑复合涂层为中心,首先阐述复合涂层及固体润滑材料的基本分类;其次综述不同制备方法的最新研究进展,重点关注工艺参数对制备陶瓷基高温自润滑涂层性能的影响及改善方法;然后归纳改善陶瓷基高温自润滑复合涂层表面摩擦学性能的关键因素,探讨了提升减摩耐磨性能的可行性和研究潜力;最后总结目前陶瓷基高温自润滑复合涂层存在的问题,主要有以下2点:(1)对复合涂层的物相分析仍以解释现象为主,没有完整的理论基础;(2)对不同制备工艺下复合涂层结构和摩擦学性能的改善手段较单一。因此提出相应的解决办法以及未来可能的发展方向:(1)研究陶瓷基体和不同润滑相、附加组元、高温环境的协同作用机理,建立系统的理论基础;(2)针对不同制备工艺的成型机理,重点研究工艺参数的协同作用对复合涂层微观结构形成的影响,扩展制备工艺的改善方法。 相似文献
9.
10.
前言 固体自润滑复合材料的应用越来越广泛,本文仅对固体自润滑复合材料CF/PTFE应用于高速伺服电机轴承的情况进行探讨。固体自润滑复合材料滑动轴承的特征是:在轴承的两相对滑动摩擦面间,没有润滑油脂的流动,其润滑靠固体材料自身来实现,这类固体润滑材料不包括涂覆料外那些在常温下是固体,在摩擦状态下室现出流体性质的材料,如石腊等。这类滑动轴承具有易起动,摩擦力小,维修方便,使用温度范围宽,耐蚀性好,能耗低,环境清洁以及不用油脂而省掉润滑系统等优点。如前西德、英国等国家已应用了固体自润滑滑动轴承的微特电机,其寿命可达到一万小时左右,而轴承的成本降低数十分之一到百分之一。在目前固体自润滑轴承材料主要分为三类:金属基自润滑复合材料,如青铜-固体润滑剂;银-固体润滑剂等;粉末冶金基自润滑复合材料-如粉末冶金青铜-浸氟塑料-固体润滑剂;非金属基自润滑受合材料,如氟塑料-增强剂-固体润滑剂等,我们多年来对多种固体润滑轴承材料在伺服电机上作了使用和寿命试验,选出了适合于作伺服电机轴承用的较为理想的材料,即碳纤维增强聚四氟乙烯固体润滑复合材料。 相似文献
11.
12.
13.
In any machining operation, the use of coolants is essential to dissipate heat generated during machining and hence to improve productivity, machinability, etc. However, the use of cutting fluids in machining operations may seriously degrade the quality of environment. New cutting techniques are to be investigated to alleviate the problems associated with wet machining. To overcome some of the problems, an attempt has been made to use graphite as a solid lubricant. This paper deals with an investigation on using graphite as a solid lubricant to reduce the heat generated at the milling zone. An experimental setup has been developed to direct graphite powder continuously onto the workpiece and tool interface at the required flow rate. Experimental studies have been conducted to see the effect of tool geometry (radial rake angle and nose radius) and cutting conditions (cutting speed and feed rate) on the machining responses such as cutting forces, specific energy, and surface finish in solid lubricant assisted machining using four fluted solid coated carbide end mill cutters. Results indicate that there is a considerable improvement in the performance of milling AISI 1045 steel using graphite as a solid lubricant when compared with machining using cutting fluids in terms of specific energy requirements, cutting force, and surface finish. 相似文献
14.
为了改善WS_2在涂料中的分散性能,将WS_2颗粒用羧甲基纤维素钠包覆并制成涂料,气压喷涂在基体表面形成固体润滑涂层。分别采用场发射扫描电子显微镜、金相显微镜和数码显微镜对固体润滑涂层及其颗粒进行了表征;在MMW-10销-盘磨损试验机上评价了固体润滑涂层在载荷128 N,转速180 r/min,600 s条件下的摩擦磨损性能。结果表明:包覆的WS_2悬浮稳定性显著提高;固体润滑涂层的磨损量及平均摩擦系数均显著降低,磨损量由77 mg降至4 mg,摩擦系数由0.180降低至0.083,且磨痕形貌比较光滑;固体润滑涂层表现出较好的润滑性能。 相似文献
15.
Grinding is a widely employed finishing process for different materials. It is inherently characterized by its high specific energy requirement unlike other machining processes. This leads to a high grinding zone temperature, which impairs the workpiece quality by inducing thermal damage in the form of surface and subsurface cracks, phase transformations, tensile residual stresses, etc. The microcracks and residual stresses induced in the surface of the ceramics during grinding can severely limit the application of ceramic components. This article deals with an investigation on using graphite as a solid lubricant to reduce friction and thereby improve the surface integrity of ground silicon carbide (SiC). An experimental setup has been developed, and experiments have been conducted to study the effect of using a graphite lubricant on the surface roughness, grinding forces, and specific energy while grinding SiC material. Results indicate that there is a considerable improvement in the performance of grinding SiC using graphite as a solid lubricant when compared with dry grinding in terms of specific energy requirements, surface roughness, and damage. The employment of graphite as a solid lubricant in ceramic grinding makes the process more economical and reliable. 相似文献
16.
M. W. Nordbakke F. Heutling M. Meyer O. Knotek 《Materialwissenschaft und Werkstofftechnik》2000,31(3):205-214
New aspects regarding sputter‐depositing dense coatings, in particular a solid lubricant of practical interest Using MoS2‐based solid lubricant films as an example, this paper focuses on approaches to preventing sputter‐deposited films from attaining columnar microstructures. This is how it becomes possible to deposit tribological coatings that are characterised by a high durability. As a result of scanning electron microscopy on microstructures, texture measurements by means of XRD, and surface analysis, focusing on sputter‐deposited MoS2 films, a concept of how to develop thick and dense MoS2‐based solid lubricant films was generated. At an early stage of film growth a dense and flawless microstructure forms. In order to make the favourable properties of these underlayers available for tribological applications, metallic intralayers were introduced, by means of which the MoS2 film growth was to be repeatedly interrupted. 相似文献
17.
磷酸二氢铝粘结固体润滑膜性能研究 总被引:1,自引:0,他引:1
无机粘结固体润滑膜与有机粘结膜相比耐高温性能优良。喷涂制备了磷酸二氢铝粘结石墨固体润滑膜,在M-2000磨损试验机上测试了涂膜在载荷100N干摩擦条件下的环块接触磨损性能并通过扫描电镜观察了磨损前后表面形貌。磨损试验表明,涂膜经过高温烘烤有利于脱除部分水分,组织更致密,其中纯石墨涂膜经过高温烘烤之后磨损量和磨损率均最低,在50min试验周期内磨损率为0.038mg/m(单位行程磨损量);在涂膜中适当添加无机颗粒有利于形成海岛结构增强体,阻止裂纹扩展。 相似文献
18.
为提高WS_2固体润滑涂层的性能,先以甲基丙烯酰氧基三甲氧基硅烷(KH570)改性WS_2颗粒,再在颗粒表面以甲基丙烯酸甲酯(MMA)原位合成聚甲基丙烯酸甲酯(PMMA)进行二次改性,并制备了WS_2固体润滑涂料涂层。采用扫描电子显微镜对涂层微观结构进行表征,采用摩擦磨损试验评价了固体润滑涂层的摩擦学性能,并采用数码相机观察磨痕的形貌。结果表明:KH570改性WS_2固体润滑涂层耐磨性能显著提高,摩擦系数也随KH570用量降低显著减小;MMA原位合成二次改性增加了涂层摩擦系数,但MMA与WS_2质量比为7∶50时,二次改性WS_2固体润滑涂层磨损量仅为纯WS_2涂层的31%。 相似文献
19.
The results of tribological studies carried out on hardened steel test bodies coated with solid lubricants are reported. The tests were carried out to assess the suitability of solid lubricant films in rolling hertzian contacts. A specially constructed concentrated contact simulator was used to determine the traction (frictional) characteristics of sputtered MoS2 and WSe2-In-Ga films. Test results obtained show that sputtered solid lubricant films are satisfactory for heavily loaded rolling contact applications as long as the slide-roll ratio is not very much larger than 0.02. Comparative tests show that burnished films yield lower traction coefficients than sputtered films indicating that there is room to improve sputtering practice further in order to enhance the tribological characteristics of sputtered solid lubricant films. 相似文献