MPV-1500型摩擦试验机在测量含油轴承摩擦系数和PV值中的应用

介绍了MPV-1500型摩擦试验机的结构,用它测量含油轴承摩擦系数和PV值的方法,以及摩擦表面温升与摩擦系数和pV值之间的关系,指出了含油轴承破坏的标志,还提出了测量中要注意的问题。     

青铜基含油轴承使用特性的研究

本文介绍了青铜基含油轴承在高速轻载条件下的试验研究结果。在69000转/分钟转速条件下,对不同的载荷和给油情况进行了1000小时的运转试验,测定了全过程的温升、摩擦系数、失油率和磨损量。试验结果与理论对比表明,所设计的含油轴承在上述运转条件下,能实现流体动力润滑,因而能长期工作。在5000~50000转/分钟和0.17~2.34公斤力/厘米2条件下,研究了不同的润滑油种对含油轴承的各项运转性能的影响。试验结果表明,在特定条件下合理选择含油轴承的油种异常重要。     

MPV-1500型摩擦试验机测定含油轴承摩擦系数

叙述了MPV—1500型摩擦试验机中滚子轴承的摩擦系数对测量含油轴承摩擦系数的影响,并探讨了如何合理计算该机的摩擦力矩问题。     

纳米铜润滑油添加剂摩擦学性能试验研究

选择轴承中使用最广泛的钢-钢摩擦副组成的摩擦体系,利用钢球的4球摩擦机,通过电子扫描电镜(SEM)观察磨斑直径和磨痕深浅,并对比摩擦系数,确定了纳米铜添加剂的最佳添加浓度为0.5%(质量分数).然后利用TLP接触疲劳试验机组模拟高速轴承的工况,考察了油溶性纳米铜添加剂的摩擦学性能;通过完全失效试验,验证纳米铜添加剂的实用性,并分析了其减摩机理.试验证明,0.5%纳米铜颗粒在轴承运转中不仅能够起到减摩抗磨的作用,而且能够延长轴承的使用寿命,提高近3倍.     

含轴油承用作磨床主轴前轴承的运转试验

为提高磨床砂轮主轴的旋转精度以及改进轴承结构,杭州机床厂将原来使用的动压轴承改成预载荷弹性变形含油轴承并取得初步成效。根据对新轴承所进行的300多小时运转试验,测得摩擦系数为0.02-0.05,温升为20℃左右,其值介于一般的流体动压轴承和铁基含油轴承之间;磨损量为10μm左右;主轴启动扭矩约为动压轴承的两倍。试验还表明,保证充分供油和把磨削力控制在额定范围以内是保证弹性变形含油轴承正常运转的两个重要条件。     

制造烧结金属含油轴承的高性能青铜粉

自润滑青铜轴承的性能决定于许多因素的综合作用,诸如精整后的密度、径向压溃强度(RCS)、含油量、表面粗糙度、施加的载荷、轴的速度及孔隙结构.压坯与烧结体的密度以及烧结时的尺寸变化(DC),在轴承制造中都很重要.这篇文章阐述了生产高使用性能烧结轴承用的一系列新的青铜粉末.对使用性能的测定表明,与用标准的预混合青铜粉末制造的轴承相比,这些轴承摩擦系数较小,温升较低且稳定,而且径向压溃强度较高.性能优异是因为连通孔隙结构较细小,从而通过极好的毛细作用可吸入大量油.在理论上,较高的RCS可使轴承具有较高的承受载荷的能力.     

TiO2和CaO对无氟保护渣流变特性的影响

采用改造后可变转速的粘度仪测定了不同氧化物和温度对高速连铸无氟保护渣流变特性的影响,并确定了不同条件下保护渣本构方程的形式(即修正后的本构方程).在实验温度条件下,保护渣为牛顿流体;加入CaO后,保护渣的表观粘度显著增加,为非牛顿流体;加入氧化物TiO2后,保护渣的表观粘度略微增加;当氧化物(TiO2 或CaO)的加入量达到一定后,保护渣为非牛顿流体.实验结果为深入研究无氟保护渣提供了新的思路和方法.     

铜、钼、铅在轴承中的新应用

用于电视录象的卷筒,电子计算机的终端机以及静电复印机等的轴承,要求具有低速、连续运转的轴承特性。最近日本粉末冶金公司研制成功“低速用低摩擦系数型烧结含油轴承”。把铜覆盖物二硫化钼、铅和石墨加到Cu—Sn合金里,使其具有润滑性能,同时也防止了强度下降。在合金中添加镍后使轴承基     

机械工业委员会通用机械局粉末冶金行业1987年优秀产品简介

名称:录音机用青铜基含油轴承用途:收录机机芯和电机材料:锡青铜粉,石墨粉,润滑油制造者:北京粉末冶金二厂简介:原材料粉末性能要求严格,产品精度要求高.由于解决了粉末处理的关键问题,采用国产粉末成功制出了录音机用轴承。产品压馈强度系数>98N/mm~2,密度5.9-7.0g/cm~3,含油率>15％(容积),摩擦系数0.04—0.06,磨损量0.006mm     

铝基烧结含油轴承研究现状

综述了铝基烧结含油轴承的发展与研究现状, 讨论了铝基烧结含油轴承制备的难点以及优化措施, 展望了铝基烧结含油轴承的发展方向。研究表明, 采用适当的烧结工艺, 可以促使铝合金粉末的烧结成形, 同时, 添加适量的合金化元素形成强化相, 能够有效提高铝基烧结含油轴承的强度, 制备的铝基烧结含油轴承具有工程实用价值。可按需制备不同组元的铝基烧结含油轴承, 通过优化烧结工艺参数, 选择适当的烧结气氛, 得到符合实际工程需要的铝基烧结含油轴承。此外, 提高烧结含油轴承的耐磨性, 开发轻质烧结含油轴承也是未来烧结含油轴承的重要发展方向。     

Use of the mathematical planning method in the selection of lubricating substances for filling the pores of sintered components of frictional units

Conclusions Measurements were made of values of the coefficient of friction of a half-journal porous sintered bearing operating with various lubricants at various loads and speeds corresponding to the conditions of operation of a spinning machine. A regression equation for the coefficient of friction has been obtained, from which the influence exerted by each of a number of factors investigated has been determined. A lubricating substance composition is recommended which lowers to a minimum the coefficient of friction of the journal bearings used in the drawing device of a spinning machine.Translated from Poroshkovaya Metallurgiya, No. 1 (205), pp. 52–54, January, 1980.     

POROUS METAL BEARINGS

Abstract

To facilitate the proper application of porous metal bearings, engineers demand a reliable method of predicting bearing performance in order that they may check the suitability of their designs. The responsibility of meeting that demand lies with the powder-metallurgy industry as much as with the many industries that use porous metal bearings. Most of the factors that determine the performance characteristics of these bearings are sensitive to temperature, and the method proposed in this paper commences with techniques for determining the temperature rise and hence the running temperature of the bearing. The temperature rise is obtained from the power loss at the bearing and the heat dissipation of the assembly. It is not possible to calculate these without knowing the bearing dimensions, and even if the dimensions are known the power loss cannot be calculated directly because this depends upon the oil viscosity and running clearance, both of which are dependent on the temperature. However, guidance curves are given for oil viscosity and clearance, which can be used in an iterative design process that converges rapidly towards the required solution. Having predicted the running temperature, assistance is given on methods of predicting the life of the bearing according to the quality and quantity of the oil at that temperature.     

MoS2和石墨对青铜基含油轴承摩擦性能的影响

通过改变MoS₂（质量分数1.0%~2.0%）和石墨（质量分数0~1.0%）的成分比例,在一定滑动线速度下,测量青铜基含油轴承承受压强的极限值,研究MoS₂和石墨含量对青铜基含油轴承的力学性能和摩擦性能的影响。结果表明:在不加入石墨的情况下,随着MoS₂含量的增加,含油轴承的负荷×线速度（pv）极限值降低,其中青铜-1MoS₂（MoS₂质量分数1.0%）含油轴承极限pv值最高,达到2.940 MPa·m·s-1;在同时加入石墨和MoS₂的情况下,随着石墨含量的增加,含油轴承的摩擦因数降低,其中青铜-1MoS₂/-1石墨（MoS₂质量分数1.0%,石墨质量分数1.0%）含油轴承摩擦因数最低,为0.038;石墨能够改善含油轴承的摩擦性能,但是会大幅度降低其力学性能。     

纳米铜自修复添加剂的制备及其摩擦学性能

采用液相还原法制备纳米铜润滑油添加剂。通过摩擦磨损试验机测试纳米铜添加剂在不同载荷下的摩擦学性能。利用扫描电子显微镜和纳米压痕仪分析纳米铜添加剂的自修复性能和机理。结果表明：纳米铜添加剂为粒径约20nm的球形颗粒，其分散性能稳定，摩擦过程中可以在摩擦表面形成低剪切强度的保护膜，具有良好的自修复性能；高载荷时，添加纳米铜添加剂的润滑油摩擦因数和钢球磨斑直径分别比原基础油减少29．1％和27．4％，表现出良好的抗磨减摩性能。     

THE EFFECT OF THE TEST FLUID AND TEST METHOD IN THE MEASUREMENT OF THE PERMEABILITY OF POROUS METAL BEARINGS

Abstract

Previous work on the determination of the fluid permeability of porous materials is reviewed, and methods for the measurement of the gas and liquid permeability coefficients of porous metal bearings are described. It is shown that the liquid permeability in porous metal is not independent of time and pressure as is the gas permeability. By the use of relatively simple experimental methods, the influence of surface-active additives in the mineral oil on the liquid permeability can be studied. By a complete understanding of the interactions between the lubricating oil and the metal surfaces of the porosity, an improvement in the performance prediction of porous metal bearings is to be expected.     

固体润滑助剂对镀铝锌耐指纹钢板表面摩擦特性的影响

在常温及高温条件下,利用表面性能分析仪和拉延设备考察了三种固体润滑助剂（聚乙烯润滑助剂、聚四氟乙烯润滑助剂及聚乙烯/四氟润滑助剂）对热镀铝锌耐指纹钢板表面摩擦特性的影响,并采用三维视频显微镜分析了镀铝锌耐指纹钢板表面划痕状态及深度。结果显示,在常温条件下,固体润滑助剂的加入不仅降低了耐指纹钢板表面的动摩擦因数,而且还提高了耐指纹钢板表面的抗磨损性和加工成型性。在高温条件下,聚乙烯润滑助剂软化导致耐指纹钢板表面润滑性能降低,并影响其加工成型性。聚四氟乙烯及聚乙烯/四氟润滑助剂的软化点较高,在高温下能够保持润滑粒子表面硬度及润滑性能,从而显著提高耐指纹钢板在高温下的表面润滑性能。     

Frictional Response of PTFE Sliding Bearings at High Frequencies

Dynamic tests were done on polytetrafluoroethylene (PTFE) sliding bridge bearings to evaluate their frictional characteristics at frequencies above 1 Hz. High frequency seismic responses of PTFE bearings are expected to occur in bridge structures in eastern North America, where the estimated ground motion is well above 1 Hz. Three different PTFE-steel interfaces were tested at frequencies ranging from 0.02 Hz to 5 Hz, with displacement amplitudes of up to ±70 mm and under confining pressures ranging from 5 MPa to 45 MPa. The experimental results showed a significant initial transient frictional response at frequencies above 1 Hz before the dynamic, steady-state, frictional behavior was achieved. This transient response is characterized by an initial high static coefficient of friction that slowly decreases to a dynamic steady-state coefficient of friction after several response cycles. Modifications to an existing mathematical friction model are proposed to take into account this initial transient frictional response.     

凹凸棒石纳米纤维用作润滑油添加剂的摩擦学性能

采用天然凹凸棒石黏土作为添加剂加入到CD15W-40润滑油中,在Optimal SRV-IV摩擦磨损实验机上测试摩擦学性能,借助扫描电镜(SEM)及其附带的能量色散谱仪(EDS)分析摩擦副的表面形貌及表面元素组成。结果表明,CD15W-40润滑油中凹凸棒石黏土的质量分数为0.4%时平均摩擦因数较基础油润滑条件下降低14.29%,体积磨损率降低59.94%;凹凸棒石黏土的加入使得磨损表面更加光滑平整,同时磨损表面氧元素含量升高。凹凸棒石黏土层链状的晶体结构和摩擦过程中复杂的理化过程是实现减磨抗磨的原因。