润滑油添加剂对陶瓷球接触疲劳的影响

利用自制的球-棒疲劳试验机研究了4种润滑油添加剂对Si3N4与GCr15钢摩擦副接触疲劳性能的影响，并借助于扫描电镜(SEM)和X射线能量色散谱(EDAX)分析了Si3N4陶瓷球表面疲劳成因及不同添加剂的抗疲劳机理。结果表明，4种添加剂都不同程度地提高了Si3N4陶瓷球的接触疲劳寿命，其中以极压抗磨剂效果较好；点蚀剥落是Si3N4陶瓷球的主要失效形式；添加剂抗疲劳的主要原因是在钢表面形成反应膜，在陶瓷球表面形成转移膜，降低了滑动摩擦力。     

磁化处理对轴承钢接触疲劳性能的影响

采用GB／T10622—1989中的对比试验方法,研究了磁化与未磁化处理的GCrl5钢的接触疲劳性能。结果表明：经磁化处理的接触疲劳寿命比未经磁化处理的提高了1．1倍。     

含纳米银粉润滑剂抗接触疲劳性能研究

制备了含纳米银粉的二相流体润滑剂，利用球-棒式接触疲劳试验机研究了纳米银粉对GCr15钢球和钢棒的接触疲劳性能的影响，并借助于扫描电子显微镜分析了钢球接触表面的疲劳点蚀形貌。结果表明：与基础油(10^#机械油)相比，含1％纳米银粉的润滑剂可使GCri5钢球的接触疲劳寿命L10提高3．54倍。其主要原因在于纳米银粉吸附于接触表面形成低剪切膜，降低了摩擦系数．减小了接触表面的切向应力，延缓了疲劳裂纹扩展速度。     

润滑油添加剂摩擦学性能的试验研究

在四球摩擦磨损试验机上对比评价了T202,T321和T406的摩擦学性能,应用扫描电镜(SEM)和X-射线能谱仪(XPS)分析了GCr15钢球表面磨痕及化学反应膜成分,对不同添加剂对轴承钢球接触疲劳寿命可能的影响机理进行了分析。结果初步验证了这几种添加剂的抗磨机理和对疲劳寿命可能的影响,也确定了其摩擦学性能差异的原因。     

氮化硅陶瓷球显微结构与滚动接触疲劳性能

利用扫描电子显微技术分析了4种氮化硅陶瓷球的显微结构，用新研制的三点接触纯滚动加速疲劳试验机，试验研究了4种陶瓷球的接触疲劳性能，并对疲劳球表面进行了显微观察。研究表明，相同试验工况下，不同的显微结构，其韧性、强度、寿命和温升明显不同。细小致密的等轴状晶粒、玻璃相少的陶瓷球的滚动接触疲劳性能优于长针状晶粒、玻璃相多的陶瓷球。     

四球机改装的接触疲劳试验机及其应用

作者将四球机改装成接触疲劳试验机，并在其上进行了一系列添加剂对接触疲劳的影响试验研究。认为该装置具有接触应力大，体积小，噪声小，一次试验耗油量小，试验系统传动稳定，试验结果可信等优点。接触疲劳试验结果认为添加剂的各种性能之间相互作用和综合效果，才是影响疲劳寿命的关键。     

摩擦系数对齿轮接触疲劳寿命的影响

通过四球试验机测试了两种极压抗磨添加剂的摩擦系以及用该添加剂分别配制的两种工业齿轮油的摩擦系数，并用动静摩擦系精密测定仪测试了两种润滑油的动静摩擦系数。同时球柱型接触疲劳试验机的实验结果证明，低摩擦系数的摩擦副疲劳寿命长，说明摩擦系数是影响疲劳寿命的一个重要因素。     

Si3N4陶瓷球与GCr15钢球接触疲劳对比试验分析

对高品质Si3N4陶瓷球和GCr15钢球在同等接触应力条件下进行接触疲劳对比试验.试验 结果表明,陶瓷球接触疲劳寿命优于GCr15钢球,且疲劳寿命离散性与GCr15钢球接近,但承 载能力不如GCr15钢球.附图9幅,表2个.     

润滑油添加剂的复合作用对接触疲劳的影响

作者利用四球机改装的快速滚动接触疲劳试验机 ,采用触逐级加载法强化试验 ,研究了硼酸酯、氯化石蜡和二烷基二硫代硫酸锌 (ZDDP)添加剂复合作用对 45钢滚动接角疲劳的影响。试验结果认为 ,硼酸酯与氯化石蜡和 ZDDP复配 ,在保证油品极压性能的前提下 ,因减摩 ,缓蚀作用而提高金属材料的接触疲劳寿命。并指出 ,研究复合功能添加剂各种性能之间的相互作用和综合效果 ,是改善润滑油添加剂影响零件接触疲劳寿命的有效手段。     

GCr4与GCr15钢冲击韧性和接触疲劳寿命对比分析

对比分桥了GCr4和GCr15钢的冲击韧性和接触疲劳寿命。结果表明，GCr4钢经感应穿透加热—表面淬火处理后，其室温与低温下的冲击韧性优于GCr15钢；不同应力的接触疲劳寿命与GCr15钢相当或略优。     

Effect of Nano-Cu Lubrication Additive on the Contact Fatigue Behavior of Steel

Effects of four different concentrations of nano-Cu lubrication additives on contact fatigue properties of GCr15 steel friction pairs were evaluated on a ball-rod contact fatigue tester. The anti-fatigue mechanisms of these additives were analyzed by means of scanning electron microscopy and X-ray photo electron spectroscopy. The test results and analyses show that all of these additives can raise the contact fatigue life of steel ball elements to a certain extent. The action of 10% additive is the better. It is confirmed that the main failure of the steel ball element is fatigue desquamation. The anti-fatigue mechanism of lubrication additives mainly accounts for forming a chemical reaction film on the steel rod and ball surface and decreasing in friction between the ball and rod, enhancing the ability of anti-wear.     

45钢离子渗硫层的接触疲劳性能研究

对离子渗硫层的接触疲劳性能进行了研究。将调质处理的４５钢进行低温离子渗硫处理后，在ＪＰ—５２接触疲劳试验机上测定了渗硫层的疲劳寿命，表明其疲劳寿命比未渗硫处理的提高一倍左右。从接触应力、润滑介质、表面缺陷和表面粗糙度等几个方面分析了渗硫层对接触疲劳性能的影响。     

Some Effects of Additives on Rolling Contact Fatigue

To study the influence of lubricant physical and chemical properties on rolling contact fatigue, a variety of base stocks and additives were evaluated with a 4-ball type fatigue machine. The effect of viscosity was found to depend on the means by which a given viscosity was achieved. Although some commonly used EP and antiwear additives had a pronounced effect on fatigue life, the direction and magnitude of the additive effect depended on the particular additive and its concentration in the blend. In addition, it was observed that the additive effect depended on the choice of base oil and ball steel. These results indicate that the chemical properties as well as the physical properties of the lubricant, can be important in rolling contact fatigue.     

钢齿轮表面合金涂层的显微结构和接触疲劳强度研究

研究了45钢齿轮轮齿表面Ni-P和Ni-Co合金涂层的显微结构和接触疲劳强度。采用电子显微镜、光学显微镜等对合金涂层进行了表面形貌、次表面组织、纵剖面界面组织、表面粗糙度、涂层的硬度和疲劳点蚀坑形貌特征的分析。接触疲劳试验结果表明,表面合金涂层能显著提高接触疲劳寿命和强度,使之与40Cr钢调质试件的相当。     

ROLLING CONTACT FATIGUE BEHAVIOR OF CERAMIC BALLS LUBRICATED BY LUBRICANTS WITH EXTREME PRESSURE ADDITIVES

An experiment is conducted to investigate the effects of lubricant10#, which contains extreme pressure additives T304 and T305, on the rolling contact fatigue (RCF) life of the contact pairs of a Si3N4 ceramic ball and a steel rod. The experimental investigation is carried out using a ball-rod RCF test rig. The results show that the extreme pressure additives increase the anti-contact-fatigue performance of ceramic balls; When the content of the additives varies from 1% to 5%, the increasing gradient of the RCF life curve decreases; And the oil sample with 1% T305 additive corresponds to the maximal gradient of the RCF life curve, with the RCF life being increased by about 10.77 times. The fatigue surface of the ceramic ball is analyzed with scanning electron microscope (SEM) and X-ray electron dispersion analysis(EDAX), and the physical model of extreme pressure additives' increasing the RCF life of the ceramic ball is proposed. It is found that the extreme pressure additives form a corrosive film and a transfer film on the surface of the ceramic ball, which decrease the surface tangential stress, and to increase the surface energy is the most effective means for increasing the RCF life.     

Fatigue Behavior of Hybrid Ceramic Ball Bearings in Liquid Nitrogen

Hybrid ceramic ball bearings, which are composed of silicon nitride (Si₃N₄) balls, ANSI 440C stainless steel rings and PTFE based composite retainers, are tested at high speed and heavy loading in cryogenic conditions. The rolling contact fatigue behavior of steel rings and ceramic balls in liquid nitrogen is analyzed. In addition, four-ball fatigue testing was done at room temperature with oil lubrication. The crush load of ball against ball in liquid nitrogen, which directly relates to the inner quality of the balls, is also evaluated. The results show that the spalling of silicon nitride balls, rather than micro pitting on the steel raceways, is the main cause for the failure of the hybrid ball bearings in liquid nitrogen. The fatigue mechanism of the ceramic balls is similar to that of ceramic balls at room temperature, but the characteristics of crack propagation are different because of differences between the cryogenic liquid medium and oil. Although most of the fatigue cracks originated from internal defects within the ceramic balls, the silicon nitride balls exhibit a high load capacity. When silicon nitride balls are loaded against steel balls, the steel balls are crushed while the silicon nitride balls do not exhibit plastic deformation. When ceramic balls with a 11.113 mm diameter are loaded against each other, crushing takes place at a nominal contact stress of 27～29 GPa.     

润滑油性能对接触疲劳影响的研究

用改装的四球机考察了不同类型的油性极压剂对接触疲劳的影响,试验证明不同类型的油性极压剂对接触疲劳的影响有显著差别,润滑油的PB、PD、ZMZ与接触疲劳性能没有关系,而长时间的磨斑直径越小,抗接触疲劳的性能越好。