固体润滑剂的特性及其应用

固体润滑剂具有许多良好的特性，其在各种机械中的应用日益广泛。本文主要介绍固体润滑剂的特性及其应用场合。一、团体润滑剂的特性不管是以固体粉末直接擦抹于摩擦表面，还是用无机或有机粘结剂将其粘结于摩擦表面或是用物理或化学方法钦覆于摩擦表面，进人际接到间的固体润滑剂是以固体润滑膜的形式发挥其作用的，因而都具备以下特性。1．摩擦特性粘着于摩擦表面的固体润滑剂在与对倡材料摩擦时，在对偶材料表面形成转移膜，使摩擦发生在润滑剂内部．这样才能表现出良好的摩擦特性——较低的摩擦系数。而且，摩擦系数随着负荷和速度的增…     

固体润滑剂

解决摩擦和磨损的重要手段是润滑。正确使用润滑剂,会带来巨大的经济效益。因而,改进现行的润滑技术,寻求新的润滑关系和新的润滑剂,已成为润滑技术领域里的重要课题。本文综述了固体润滑剂种类、特点、性能及其应用,对机械设计和生产应用有一定的参考作用。     

新一代润滑剂——超细金属粉固体润滑剂

润滑油是机械运转的血液,机械和装备的使用寿命和经济性与油料的质量性能和合理使用有密切关系.众所周知,在润滑油中加入减摩剂可提高其抗摩性能,减少摩擦阻力,延长机器部件的使用寿命.目前减摩剂的品种繁多,但大体可分为两类:一类为油溶性有机化合物,它们易与润滑油混合,可均匀地加入各类润滑油中,有效改变润滑油的品质,但在摩擦过程中可能产生有害成份,特别是当油温较高时,可能对有色金属(如含银、锡)的轴承材料起腐蚀作用;有些油溶性有机添加剂易分解消耗,需不断补充.另外这种添加剂的合成     

耐高温无机固体润滑剂的发展

随着航空、航天、核能等尖端技术的发展,对材料的耐高温性能及其在高温条件下的润滑提出了更高要求,如绝热柴油发动机轴承衬垫的工作温度达600—1000℃;汽车燃汽涡轮发动机,其工作温度为260—1100℃;其主轴温度达650℃;航空燃汽涡轮发动机的工作温度为250—1000℃;超音速飞机中控制装置的轴承表面温度达800℃;航天飞机控制装置的表面摩擦密封湿度达850℃,等等.八十年代以来摩擦学界已将此列为摩擦学应解决的重点课题之一.普通润滑油,润滑脂及其他有机润滑剂已不可能在这样高的温度下使用,而无机固体润滑剂,如一些氧化物、氟化物、软金属等,以其优异的耐高温性能引起人们的重视.近年来,为解决高温工程材料在高温条件下的润滑问题,采用无机固体润滑剂已被证明是一条有效途径.     

机械加工中使用固体润滑剂的经验

机械加工通常使用以油基或水基并添加各种作用的添加剂作润滑剂,解决加工中的润滑冷却。为了改善润滑性能可在油基或水基切削液中添加各种各样的固体润滑剂,如石墨、二硫化铜、氧化铝、四氧化三铝、硼酸盐、聚丁烯和各种脂肪酸金属皂等,以取得良好的加工质量与高生产效率。     

固体润滑剂应用的研讨

论述了固体润滑膜的干法制备、湿法制备、粉末喷涂、复合镀和涂擦成膜等方法的工艺及配方；固体润滑剂在压力加工、齿轮、导轨、气缸与活塞、轴承等方面应用；固体润滑剂做成背衬型材料、镀嵌型材料、油脂中添加固体润滑剂等的特性与应用．     

High-temperature solid lubricating substances

An evaluation of the results of studies of the friction of solids at elevated temperatures in a vacuum and in air has enabled the identification of promising materials for use as solid-lubricating substances within various temperature ranges. Solid-lubricating substances (solid greases) are commonly incorporated into composite materials and coatings. When several solid greases are introduced into a composition, their action results in synergism.     

Modified solid lubricating coatings based on tungsten diselenide

The dependence of the wear rate of WSe₂-Ga/In coatings on the environment conditions (air, vacuum, temperature) and counterbody material is obtained. The formation of films in the friction contact zone is shown to occur owing to the transfer of individual lubricant components and their reactions with each other and with atmospheric oxygen.     

Evaluation of the friction of WC/DLC solid lubricating films in vacuum

The accuracy of nanopositioning is to a large extent limited by the friction-caused errors, particularly in vacuum environments. An investigation of the friction behaviour of sp²-bonds dominating diamond like carbon (DLC) coatings and WC_1−x/DLC, WC(N)/DLC multilayer coatings, which are considered to be used in nanopositioning in vacuum, have been performed by a vacuum microtribometer. By using an atomically smooth Si sphere as a counterface, the reciprocating sliding friction was measured at a normal load <5 mN, and running speed at a 1–100 μm/s in ambient air and in ultra high vacuum (UHV) at 10⁻⁷ Pa, and correlated with microstructures and properties of the coatings. When tested in UHV, the coefficient of friction (COF) for pure DLC coatings (thickness: 700 nm) changes significantly between 0.2 and 0.4. Once the thickness of DLC layers is limited to 5 nm by formation of multilayer coatings, the COF in UHV decreases by nearly one order to 0.02–0.05. We suggest that the deformation of DLC films and the transfer films determines COF. Thick DLC coatings can induce more plastic deformation and consumes more energy in sliding resulting in a high COF. Thickening of the transfer film in running leads to a continuous decrease of COF since the deformation of the transfer films turns easier. The low COF of multilayer coatings is mainly due to their confinement of the thickness of DLC films. A consistent velocity-strengthening frictional behaviour of both WC_1−x/DLC and WC(N)/DLC coatings in UHV indicates that the transfer films acting as a thin layer of granular material. Further study of the friction behaviour with the presence of such granular materials might be interesting for the further development of tribological coatings for vacuum applications.     

油气润滑使用的现场研究

介绍了油气润滑系统在使用中最容易出现的几种情况及其处理方法,为油气润滑系统的现场使用提供了很好的指导作用;实例分析说明了油气润滑系统的优点.     

固体润滑轴承在轧钢机运输辊道上的应用

用铁基铬钨硫化物固体润滑复合材料轴承替代轧钢系统恶劣工况条件下使用的铜瓦及滚动轴承类备件,在同等条件下使用寿命提高10倍以上,是轴承类备件更新换代的良好途径.     

润滑系统在大型机组中的应用

润滑系统在各类机械转动设备中起着非常重要的作用,在设备的保养及维护中,都对润滑的各种参数及控制有详细的说明及应用。主要是对炼油装置大型机组的润滑系统中的主要仪表控制系统进行论述说明,从仪表方面了解润滑系统在机组中的重要作用。     

智能PID算法在调和罐液位控制中的应用研究

运用RBR产生式规则专家系统结合常规的PID算法实现了对于调和罐液位的恒定控制.知识库采用无相交集的事实知识构成,对于任何情况都能找到唯一的匹配条件,触发相应的控制规则.算法通过PLC中的梯形图在液位控制系统中进行了验证.应用表明算法相比于常规PID控制具有更好的稳定性,可靠性和环境适应性.     

变频技术在调和油罐液位控制中的应用研究

针对润滑油调和油罐的液位控制问题首先阐述了离心泵的流量调节原理.通过对恒速离心泵流量调节方式和变频调速离心泵流量调节方式进行比较,阐述了变频技术应用在离心泵流量调节中所具有的高效和节能特点.通过串联调节方式运用变频技术实现调和油罐恒定液位控制,给出了系统的具体设计方法和步骤.     

Wear behavior of Pb–Mo–S solid lubricating coatings

Amorphous Pb–Mo–S coatings 200 to 510 nm thick were deposited by dual ion-beam deposition (IBD) onto steel and Si substrates. Coating wear studies were performed using ball-on-flat reciprocating sliding with steel ball counterfaces in dry air. Tests were run between 1 and 100,000 sliding cycles, and wear depths measured by interference microscopy. Morphology and chemistry of the as-deposited coatings and worn surfaces were investigated with optical microscopy, micro-Raman spectroscopy and cross-section high resolution transmission electron microscopy (HRTEM). Pb–Mo–S coatings were found to be quite wear resistant; no more than 25% of the coating thickness was removed by 10,000 sliding cycles. Two wear mechanisms were identified. At the nanometer scale, wear proceeded in a two-part process: transformation of the coating surface to MoS₂, then layer-by-layer removal of MoS₂. At the micrometer scale, wear occurred by plowing. The long endurance of Pb–Mo–S coatings was attributed to slow wear of the coatings, with lubricant redistribution processes playing a minor role.