复层铁基粉末冶金材料的制备及其摩擦学性能分析

采用粉末冶金工艺制备基体致密、表层多孔含油的双层复合铁基粉末冶金材料,用HDM-20端面摩擦磨损试验机评价其摩擦磨损性能。结果表明,当复层材料表层的孔隙率约为23%时,试样稳定运行时间长,减摩耐磨性能好;与相近孔隙率的单层材料相比,复层材料的减摩耐磨性能与承载能力得到明显提高。     

摩擦试验条件对凹凸棒石黏土润滑油添加剂摩擦学性能的影响

采用往复滑动磨损试验机评价凹凸棒石黏土天然矿物材料作为润滑油添加剂的摩擦学性能,利用4因素3水平正交试验方法系统研究摩擦过程中载荷、往复频率、滑动时间和凹凸棒石黏土含量对其作为添加剂的抗磨、减摩性能的影响。摩擦过程中,通过原位测量摩擦表面接触电阻的变化,监测凹凸棒石黏土形成摩擦反应膜的动态形成过程。摩擦学试验结束后,利用扫描电镜(SEM)和X射线能谱仪(EDS)分析磨损表面的形貌与元素组成,探讨凹凸棒石黏土添加剂的减摩润滑机理。结果表明,表面修饰棒状凹凸棒石黏土天然矿物材料作为润滑油添加剂具有优良的摩擦学性能,含凹凸棒石粉体润滑油作用下的摩擦表面形成了一层富含Si、Mg、Al、O等元素的不导电摩擦反应膜,并分布大量纳米尺度的硅酸盐颗粒物,从而显著降低摩擦,减少磨损。摩擦过程中载荷、往复频率、摩擦时间和凹凸棒石添加量4个因素对凹凸棒石添加剂减摩和抗磨性能影响的主次顺序均为:载荷添加量往复频率时间。     

铁基金属塑料复合材料及其摩擦磨损性能

金属塑料复合材料是近年来在粉末冶金工艺基础上发展起来的一种新型减摩材料。本文介绍了铁基金属塑料复合材料的制造方法,研究了不同加碳量对基体机械性能的影响及不同载荷下的摩擦磨损性能。试验结果表明,该材料具有较高的机械强度和较好的摩擦磨损性能。当载荷在0-25kgf范围内,其摩擦磨损性能达到DU材料的水平。装车试验结果还表明,它的使用寿命为同类铁基含油轴承的二倍多。     

速度与载荷对无铅铜铋轴承材料摩擦学特性的影响

采用粉末冶金法制备无铅铜铋双金属轴承材料,并在HDM-20端面摩擦磨损实验机上进行油润滑条件下的摩擦磨损试验,分析速度、载荷对其摩擦学性能的影响。结果表明:摩擦因数随摩擦速度、载荷的增加而减小,其磨损量、摩擦副表面温度均随速度、载荷的增加而增大;摩擦磨损过程中低熔点组元铋的析出起着较好的减摩、抗粘着作用,并存在铋的析出、熔化、磨损脱落的循环过程。     

用于高粘附性机车的车轮／钢轨材料的磨损和摩擦特性

当新型机车在较高的粘附力水平下运行时，车轮和钢轨材料在干燥条件下的磨损和摩擦性能将发生变化。因此，对可供选择的机车车车轮材料在高粘附条件下的磨损和摩擦行为进行评估具有重要意义。本文论述了车轮和钢轨材料组合的磨损及摩擦特性的实验研究结果。     

蛇纹石超细粉体作润滑油添加剂的摩擦学性能

考察平均粒径为1.0μm的表面修饰蛇纹石超细粉体作为50CC润滑油添加剂对钢/钢摩擦副的润滑性能,研究超细粉体添加量(质量分数)对摩擦学性能的影响.通过对磨损表面的形貌、元素及微观力学性能分析,探讨蛇纹石超细粉体作为添加剂的抗磨、减摩机制.结果表明,蛇纹行超细粉体可显著改善50CC润滑油的润滑性能,降低钢/钢摩擦副的磨损,其最佳添加量为1.5%.蛇纹石超细粉体的减摩润滑机制在于:1)在铁基摩擦表面形成高硬度、低弹性模量的氧化膜,有效降低接触应力和磨粒磨损;2)释放出Al2O3杂质颗粒嵌入摩擦表面并形成微坑和孔洞,起硬质点颗粒增强与微孔储油的双重抗磨、减摩作用;3)摩擦过程中粉体粒径得到细化,形成具有减摩润滑作用的纳米级蛇纹石"第三体"颗粒.     

SF-1填充PTFE表面层配方的摩擦特性研究

以填充改性PTFE为表面层、青铜粉为中间层、背面为钢板的SF-1三层复合自润滑轴承材料，在工程上的应用日益广泛。该材料表面层的配方和性能，是整个材料的摩擦特性的决定因素。本文针对高压齿轮泵轴承的应用场合，设计了几种填充PTFE的表面层配方，在Amsler摩擦磨损试验机上测定不同表面层配方的SF-1材料的摩擦和磨损性能，并优选出两种配方的SF-1材料制成滑动轴承试样，在轴承试验机上进行极限PV植试验评价，同时讨论了SF-1表面层配方中固体润滑剂对摩擦特性的影响及耐磨机理。     

自润滑材料滑动摩擦失效分析

通过滑动摩擦磨损实验,评价试样的磨损性能,结合自润滑材料的摩擦特性（μ-n）曲线和自润滑滑动摩擦磨损机理,利用SEM研究摩擦磨机理,得知自润滑材料失效的实质是：在滑动摩擦的后期,自润滑向干摩擦过渡,最终转变为干摩擦,而干摩擦的磨损量比自润滑的高3个数量级,使材料的磨损量急剧升高,材料因磨损量过大而失效,其磨损机理粘着磨损。     

MoS2对镍基自润滑材料摩擦学特性的影响

详细地研究了在Ni- 2 0Cr合金粉中添加MoS2 ,通过热压法制备得到的高温自润滑材料的摩擦学特性。研究表明 ,当MoS2 的添加量在 2 0 %左右时 ,所得到的材料具有最佳的摩擦磨损性能。在热压过程中MoS2 发生了热分解 ,并与合金中的铬反应生成了CrXSY(x/y =2 /3～ 1 )型硫化物共晶体 ,这种化合物在高温下可以变软或熔化 ,在摩擦面之间形成润滑膜 ,并具有转移性 ,从而具有减摩性能。     

镍基高温自润滑材料的摩擦学特性研究

详细地研究了在Ni-20Cr合金粉中添加MoS_2,通过热压法制备得到的高温自润滑材料的摩擦学特性。研究表明:当MoS_2的添加量在20％左右时,所得到的材料具有最佳的摩擦磨损性能。在热压过程中MoS_2发生了热分解,并与合金中的铬反应生成了Cr_XS_Y[x/y=(2/3)～1]型硫化物共晶体,这种化合物在高温下可以变软或熔化,在摩擦面之间形成润滑膜,并具有转移性,从而具有减摩性能。     

Fe-Cu-Me铁基减摩材料的研究

研究了Fe-Cu-Me铁基减摩材料的成分配比和烧结温度对其物理力学性能的影响。结果表明,在最佳成分配比和低温烧结条件下,Fe-Cu-Me材料的综合性能良好,在一定工况下可替代ZQ_Sn6-6-3合金,可望成为节能、节材效果显著的高性能廉价减摩材料。     

Fe－Cu－Me铁基减摩材料的研究

研究了Ｆｅ－Ｃｕ－Ｍｅ铁基减摩材料的成分配比和烧结温度对其物理力学性能的影响。结果表明，在最佳成分配比和低温烧结条件下，Ｆｅ－Ｃｕ－Ｍｅ材料的综合性能良好，在一定工况下可替代ＺＱ＿Ｓｎ６－６－３合金，可望成为节能、节材效果显著的高性能廉价减摩材料。     

Sintered Antifriction Materials for Use at Elevated Temperatures

The mechanical and antifriction properties of three types of new materials were investigated. These were based on powder scrap of steel R6M5, nickel, and the powder metallurgy nickel alloy ÉP975. The metallographic structures of the new materials were studied. It was shown that the developed materials can be successfully used in friction units operating at 500, 700, and 900°C, respectively.     

361441

The tribological properties of materials were studied under conditions which model the collective and individual effects of outer space factors (vacuum, cryogenic temperatures, solar electromagnetic radiation). The behavior of aerospace materials (structural materials, self-lubricating composite materials, antifrictional solid lubricant coatings, wear-resistant coatings, etc.) were investigated. An approach to the design of materials for friction units is proposed, based on the concept that the materials of a friction pair are a complex self-organizing system. This made it possible to substantially expand the range of application of materials and coatings, and aided in the creation of new antifriction materials with pre-determined properties.     

Sintered ferrous antifriction materials for arduous operating conditions

Summary The main methods by which the load carrying capacity of ferrous antifriction materials may be raised are to increase the strength of their metallic matrix by suitable alloying and to decrease their coefficient of friction by the addition of various sulfides. Researches in this field have led to the formulation of a new class of sulfidized ferrous materials. The investigation has shown that, if the load carrying capacity of a material is to be increased, the latter must contain structurally free graphite and sulfides, which secure the formation of stable working films with a low coefficient of friction. The best antifriction properties for the type of material investigated are ensured by a pearlitic-ferritic structure with a pearlite content of not more than 50%.The highest antifriction properties are exhibited by iron-graphite base materials containing 4% zinc sulfide with additions of 1% tin and 1% elemental sulfur.Translated from Poroshkovaya Metallurgiya, No. 8(56), pp. 39–45, August, 1967.     

Antifriction composite materials for friction joints of centrifugal equipment

Mechanical and antifriction properties of promising copper-based powder materials are examined. The metallographic structure of the new materials is studied. It is shown that copper-based composite materials can be successfully used instead of babbits for friction joints operating at high sliding speeds.     

Development of antimony-based impregnating alloys to produce electrographite frame composite materials

The properties of antimony-based alloys used as an impregnating metal in electrographite composites for creating antifriction composite materials are studied. The linear shrinkage, penetrability, corrosion resistance, and mechanical strength of the alloys are experimentally determined.     

Antifriction properties of some composite sintered packing materials. II

Summary The addition of more than 20 vol.% of solid lubricants to the materials investigated is undesirable, because it adversely affects their strength properties and increases their coefficients of friction and specific wear, with increasing rubbing velocity and pressure, high temperatures are generated in the friction surface zone, resulting in the oxidation of the solid lubricant and the metallic matrix of the materials and formation of oxides on the surface. The presence of oxides on the friction contact surface inhibits the propagation of thermal seizure processes, in consequence of which specific wear and the coefficients of friction decrease. Conversely, the burning out of graphite solid lubricant is responsible for the deterioration of the antifriction properties of materials. As a result of this, with increase in rubbing velocity, the coefficients of friction and specific wear of materials with additions of chemically stable solid lubricants decrease, while those of nickel-graphite materials increase.On the basis of the investigations described, natural mica (phlogopite) and boron nitride may be recommended as substitutes for graphite as solid lubricants in packing materials. From the point of view of operation in packing elements of gas-turbine engines, the best combination of antifriction properties is offered by sintered composite nickel-mica and 20Cr-80Ni alloy—boron nitride materials.Translated from Poroshkovaya Metallurgiya, No.9(45), pp. 61–66, September, 1966.     

Antifriction and Friction Cermet Materials

The experience in designing antifriction and friction cermet materials using the method of powder metallurgy is presented. The antifriction sintered materials with increased load-bearing capacity as well as for exploitation in vacuum and inert media are considered. The ways are analyzed for increasing friction coefficient and wear resistance of sintered friction materials.     

Production and properties of metal-PTFE antifriction materials from atomized bronze powders

Conclusions An investigation into the sinterability of loosely poured atomized bronze powders has established that the porosity of resultant sintered bronze skeletons depends on the particle size and shape. The shape of the bronze powder particles has some effect on the antifriction characteristics of a metal -PTFE material, but its coefficient of friction and wear resistance are affected more strongly by the composition of a solid lubricant introduced into the pores of its sintered skeleton. Using a nonspherical rather than spherical bronze powder gives a bronze saving of 15–20% without affecting the good antifriction properties of metal-PTFE materials, by increasing the porosity of their skeletons. Replacing molybdenum disulfide with graphite substantially increases the wear resistance of two-layer metal-PTFE materials and markedly decreases their cost, since the price of molybdenum disulfide is more than 20 times that of graphite.Translated from Poroshkovaya Metallurgiya, No. 9(273), pp. 30–34, September, 1985.