液力挤压高比重钨合金材料的润滑与摩擦

应用流体润滑理论研究了液力挤压大变形高比重穿甲弹芯钨合金材料的润滑与摩擦,并对液力挤压中形成连续滑润膜的必要条件进行了公式推导.结果表明,坯料的表面状态、润滑剂和液体介质的种类影响液力挤压高比重钨合金材料的润滑和摩擦.当坯料用二硫化钼润滑脂润滑并以蓖麻油或其它矿物油作为压力介质时,就可获得最有利的摩擦状态和润滑状态.且当坯锭移动速度达到某一数值以上时,还可以形成连续的滑润膜.而连续滑润膜的形成是实现稳定挤压、改善挤压制品质量、消除粘着滑移的最有效手段.     

水润滑UHMW-PE轴承在特殊条件下的应用研究

UHMW-PE是一种线性结构的工程塑料，具有优异的物理性能和机械性能。可用作水下润滑轴承。通过有限元法验证了应用于某轧钢厂加热炉辊道的UHMW-PE轴承(替代原金属轴承)的合理性，论证了应用的可行性。实践证明。UH-MW-PE轴承代替原金属轴承使用寿命由1～2个月提高到6个月以上，改造24组辊道。年节省直接费用达30万元。     

Characterization of tribo-layers on self-lubricating plasma-assisted chemical-vapor-deposited TiN coatings

Recently, several new solid lubricants and modern lubrication concepts have been developed to achieve lower friction and wear and thus longer lifetime in severe tribological applications. The aim of this study is to characterize tribo-layers formed during ball-on-disc testing on low-friction, Cl-containing TiN coatings deposited by plasma assisted chemical vapor deposition and to clarify their formation mechanism. Characterization of the transfer layers was done by optical microscopy, optical profilometry, Raman spectroscopy, Auger electron spectroscopy and X-ray photoelectron spectroscopy. Differential scanning calorimetry was used to provide information on the chlorine-influenced chemical reactions of the coatings in ambient air. Iron oxide layers of a thickness in the nm-range have been found on low-chlorine containing TiN coatings (<3 at.% Cl) showing friction coefficients of approximately 0.8, whereas on TiN coatings with higher chlorine contents (>3 at.% Cl) rutile layers were preferably formed, resulting in friction coefficients below 0.2. This self-lubrication mechanism can be explained by the in-situ formation of easy-shearable titanium oxides in the contact zone in the presence of humidity and oxygen.     

Diffusion-limited evaporation of thin polar liquid films

The stability of evaporating very thin films of a polar liquid is investigated. The microscopic interaction with the substrate and capillarity are taken into account in a lubrication equation. The stability of a flat interface is studied when evaporation is limited by the diffusion of the vapour in the gas phase. The evaporation rate is computed and evaporation is shown to be stabilizing. A stability phase diagram is obtained. A weakly nonlinear analysis leads to a film-thickness amplitude equation that is non local in space. Physical consequences of the results are eventually discussed.     

适用于中小型水轮机上的结构新技术

介绍了适用于中小型水轮机上的集成安装式、无水冷却和无油操作及润滑等方面的结构新技术，并说明了这些技术的应用将会带来良好的经济效益和环保效益。     

热轧润滑应用效果的因素分析

介绍了板带热轧润滑的机理，分析了影响热轧润滑使用效果的因素，同时提出进一步改善热轧润滑效果应重视的问题。     

粉末冶金静电模壁润滑中润滑剂粉末的荷电影响因素

粉末冶金静电模壁润滑是一种新颖的润滑方式。本文通过试验研究了在粉末冶金静电模壁润滑技术中润滑剂粉末荷电情况的各种影响因素，包括润滑剂种类、电压和输粉管长度，并对其进行了初步理论分析。结果表明：硬脂酸锌荷电性能最好，不存在荷电阀门值(能使润滑剂粉末荷电的最低电压)，而EBS蜡、W-special蜡及硬脂酸锌和EBS蜡的各种混合粉均存在一荷电阀门值；另外，输粉管长度越短，EBS蜡的荷电阀门值越高，荷电性能越差。     

Influence of surface roughness on friction and scuffing behaviour of cast iron under sparse lubrication

Friction and scuffing behaviour of grey cast iron as influenced by the surface roughness under sparse lubrication conditions is studied. The studies are carried out on a three-shoe-on-disc machine under the conditions of parallel sliding. The experiments were conducted at three oil supply rates of 0.10, 0.22 and 0.36 μg/cm² per contact obtained through a mist oiling system and with specimens of cast iron shoes of different roughness values, Ra, between 0.04 and 2.0 μm against a 0.55% C steel disc. In a step load procedure, the friction torque at the end of each load step and the scuffing load are the major parameters measured. Results of friction and scuffing behaviour as a function of roughness and oil supply rates have been discussed.     

粉末涂料固体润滑膜滚动/滑动复合干摩擦磨损特性研究

在M-2000磨损试验机上考察了经过一次处理和经两次处理的40Cr钢环表面喷涂3种粉末涂料型固体润滑膜(P型、H型、E型)试样,在线载荷为104N/m、相对滑动速度为0.042 m/s、干摩擦滚动/滑动复合磨损条件下的摩擦磨损性能,通过扫描电子显微镜(SEM)对试样磨损表面以及磨屑进行了显微观察。结果表明:底材经过一次处理(化学底膜处理)的复合固体润滑膜试样,P型和E型在磨损后期的摩擦因数分别稳定在0.38和0.32,而H型在0.40左右跳动;P型和H型的涂层磨损脱落期为60 m in左右,E型为120 m in左右;质量磨损从小到大顺序为P型相似文献   

Reduction of Friction by Functionalised Viscosity Index Improvers

A range of functionalised polymethacrylate copolymers have been synthesised with different functionalities, polymer architecture and molecular weight. It is shown that appropriately functionalised block copolymers give enhanced film thickness and greatly reduced friction under low entrainment speed conditions, even with polymer concentration as low as 1% wt. This behaviour almost certainly results from the formation of an adsorbed brush-like film of thickness ca 20 nm on each polar surface. These films provide a highly viscous inlet that promotes fluid entrainment and thus maintains a separating film down to very low entrainment speed. The adsorbed polymer films are also able to maintain separation in stationary contact conditions. Randomly distributed copolymers do not show this type of behaviour. The friction reduction observed is more effective in unidirectional, mixed sliding–rolling than in reciprocating, sliding conditions. However, it is found that functionalised polymers and conventional organic and molybdenum-based friction modifiers can be combined to provide effective friction reduction over the whole range of rubbing conditions.