基于胎面扰动的轮胎多边形磨损机理探讨

通过建立基于胎面扰动的非均匀磨损动力学模型,验证了轮胎多边形磨损可以由胎面扰动引起,分析了基于胎面扰动造成轮胎非均匀磨损的机理,得出多边形磨损边数主要由轮胎的转动频率和胎面的固有频率决定的结论,并得到了轮胎磨损边数的计算公式.     

汽车轮胎异常磨损的原因探究及预防

轮胎是汽车的主要运行材料，是汽车与地面之间的传力元件，因此，轮胎容易产生异常磨损，轮胎也是汽车上的易损件之一。汽车轮胎异常磨损现象有多种，轮胎的磨损原因也有多种。文中详细地分析了汽车轮胎异常磨损的原因，并提出预防轮胎异常磨损的措施。     

谈橡胶轮胎的磨损因素与使用要点

汽车轮胎一般属于消耗品,每天都要和粗糙的路面深度接触,磨损自然是难免的事情,使用一段时间之后就必须更换。但有些异常的磨损情况是会缩短轮胎使用寿命的,而且有时可以从轮胎的磨损程度发现车辆隐藏的故障,所以切不可掉以轻心。一般来说如果车辆没有问题,轮胎的磨损就应该是均匀的,要是发现车辆轮胎的磨损并不均匀,那就要及时检修了。     

叉车轮胎的非正常磨损及预防

简述预防叉车轮胎非正常磨损的重要意义及叉车轮胎在使用中的六种磨损情况;从使用、行车机构技术状况变化、驾驶技术三方面,分析了非正常磨损的原因;从加强轮胎维护、提高底盘维护质量、合理选择和搭配轮胎、装载平衡等方面阐述了应采取的预防措施。     

基于解析方法的轮胎磨损颗粒物运动轨迹分析

轮胎磨损颗粒物的运动轨迹分析对磨损颗粒物的捕集具有非常重要的理论意义。建立了轮胎磨损颗粒物的运动微分方程,分析了车速和磨损颗粒物粒径对其运动轨迹的影响,设计试验验证了模型的正确性。结果发现：较小粒径（10μm）的磨损颗粒物与较大粒径（500μm）的磨损颗粒物的飞扬区间变化较小,粒径100μm左右的磨损颗粒物的飞扬区间变化较大。覆盖件150～250mm的高度区域是轮胎磨损微小颗粒物（小于100μm）的散射聚集区域。     

装载机轮胎的损坏及应对措施

1．损坏形式 （1）胎冠过度磨损造成胎冠过度磨损的原因有4个方面。①驱动轮滑转。装载机负荷过大,轮胎相对附着力降低,驱动轮滑转,造成胎冠过度磨损。驱动轮在行驶接触面上留下明显的炭黑痕迹,而沿轮胎圆周方向则留下长短、深浅不一的划痕。     

磨损对轮胎侧偏刚度和回正刚度影响的研究

基于轮胎六分力测试结果,研究不同磨损状态下轮胎的侧偏力学特性,得出轮胎侧偏特征参数随着轮胎磨损量的变化规律。通过建立胎面磨损模型阐明轮胎磨损特性变化的机理,得到胎面刚度与磨损量的表达式,之后根据该表达式和考虑轮胎磨损状态的轮胎刷子模型,建立考虑胎面磨损的轮胎复杂刷子模型。通过模型推导得到磨损量与轮胎侧偏刚度、回正刚度的关系,以该关系为UniTire轮胎模型的建模基础表达公式,建立考虑磨损的UniTire侧偏模型。为验证模型的正确性,采用3种磨损状态的侧偏数据进行参数拟合,得到考虑磨损的UniTire侧偏模型,并预测其他2种磨损状态下的轮胎侧偏特性。预测模型的仿真结果与试验结果之间的误差较小,有效证明了考虑磨损的UniTire侧偏模型的预测能力。本研究有助于完善UniTire轮胎模型,为UniTire模型室内外扩展应用提供理论和技术支持。     

装卸机械的磨损形式及对策

在对装卸机械的磨损进行观察和思考的基础上，分析了磨损的2种形式，并针对磨损形式的特征提出了装卸机械磨损的对策和补偿方法，取得了良好的经济效益。     

PCD刀具加工铝合金刃口磨损与对策

对PCD刀具刃口磨损的形式进行了分析,确定PCD刀具在加工铝合金中磨损的主要形式为聚晶层破损,针对聚晶层破损这一磨损的方式,提出了应对策略。     

轮胎异常磨损机理及对策

轮胎是支撑车辆重量，传递驱动和制动力矩，提高吸振和包络能力的总成部件。应具有一定的抗磨性、低滚动阻力、耐久性、保证转向稳定性和安全性等特点。论述了轮胎与路面之间的摩擦机理；并从使用、检修和道路影响等方面，分析轮胎异常磨损的影响因素及原因；提出减轻轮胎磨损的对策。     

基于有限元方法的轮胎磨损特性研究

在基于有限元法的轮胎磨损性能评价方法的基础上,建立了205/55/R16型子午线轮胎2种胎面结构的有限元模型。使用ABAQUS软件的显式分析方法获得轮胎接地区域节点在汽车行驶过程9种工况下的法向反力和滑移速度,通过摩擦能量损失和磨损量之间的关系,求得轮胎在组合工况下行驶特定里程的磨损量。光面轮胎的磨损量明显小于花纹轮胎磨损量的仿真分析结果,说明了仿真分析方法的有效性。同时,通过对ABAQUS软件的二次开发,实现了轮胎接地区域摩擦能量损失率分布的实时描述。     

Numerical calculation of irregular tire wear caused by tread self-excited vibration and sensitivity analysis

Tire wear negatively affects vehicle safety and riding comfort. Abnormal wear is more dangerous and wears tires out more quickly. In this paper, numerical and sensitivity analyses of polygonal wear caused by unstable vibration are presented. The model used for this study was based on the works of Sueoka. Tread self-excited vibration was analyzed in a quantitative sense, which was qualitatively different from the work of Sueoka. Wear was plotted on tire circumference visually. The mechanism governing polygonal tire wear was investigated as that both the polygonal wear and the standing wave are caused by two types of tread vibrations that only differ in the extent of the tread vibration. Sensitivity analysis shows that decreases in tread mass and stiffness and increases in tread damping lead to noticeable reductions in tire wear. This information could help tire manufacturers produce tires that exhibit less wear caused by tread vibration.     

Tire wear by ablation

The transient temperature profile of a slipping tire is calculated by taking into account the frictional heating due to slip, temperature build-up due to hysteresis, convection and radiation loss into the air, and conduction cooling into the ground. Specific attention is directed to the calculation of tire surface temperature. Calculated surface temperature shows a value which may exceed the melting point of tread rubber. The phase change of the tread rubber at the surface leads to a particular wear mechanism. Wear of the tire is calculated for the transient process which occurs at the contact area between tire and ground.The governing equations for temperature profile and the associated wear process are solved numerically by a finite difference technique. Tire surface temperatures for different service conditions agree well with the available data for automobile tires. Tire wear data agree with those reported for airplane tires. The proposed wear model may be applicable to automobile tires when the service condition is severe.From the thermal analysis one can see the effect of surface properties of both tire and ground on the wear process. Other parameter studies provide some information about the effects of some important factors on tire wear.     

子午线轮胎的非自然平衡轮廓设计及性能分析

在分析现有子午线轮胎非自然平衡轮廓设计理论的基础上,以12.00R20和385/55R22.5两种规格载重子午线轮胎为研究对象,利用酒井秀男非自然平衡轮廓理论、Frank非自然平衡轮廓理论及新非自然平衡轮廓理论对胎体轮廓进行设计。利用有限元分析技术,从轮胎磨损、滚动阻力、抓地力等方面,对三种轮廓理论设计的两种规格轮胎的性能进行综合对比分析。结果表明：酒井秀男的设计理论适合于断面高宽比较大的轮胎;Frank的设计理论适合于断面高宽比较小的轮胎;新非自然平衡轮廓理论设计能够减小轮胎磨损,降低滚动阻力等;轮胎胎体轮廓设计对轮胎性能具有重要影响,尤其对滚动阻力具有显著影响,新非自然平衡轮廓设计理论为低滚阻轮胎设计提供了方向参考;新非自然平衡轮廓设计理论可解决轮胎性能间不相容的难题。     

Ceramic wear maps

Ceramic wear maps have been developed to elucidate the complex interactions of the operating parameters, environments, and wear mechanisms. This paper summarizes these interactions for four ceramics, alumina, yttria-doped zirconia, silicon carbide and silicon nitride. Wear maps of these ceramics are systematically constructed using measured data under dry sliding, water, and paraffin lubricated conditions. For each material, different wear level regions acid wear transition zones are identified as a function of operating conditions and lubrication conditions. Wear mechanism studies performed within each wear region give rise to the wear mechanism maps. These maps facilitate material comparison and selection. The knowledge of wear, wear transitions, and wear mechanisms for a material pair enables realistic wear model development. One outcome of this approach is the recognition that a single wear model for a material pair cannot cover all operating conditions and environments.

As wear maps are constructed today, they are material pair specific. Within a material pair, there are microstructural dependence and surface properties influence. These parameters can change substantially for a given chemical composition of the material. How to incorporate these factors into the wear map research remains an issue. The search for a universal parameter such as the “asperity temperature” in Ashby's wear map continues in spite of mounting evidence that this may not be practical or feasible. But the hope remains that some parameters can be identified to normalize a large number of materials, operating conditions, and environments for tribological applications. Systematic wear maps are the first steps in this direction.     

The Slow-Speed Wear Behavior of Case-Carburized Gears Lubricated with NLGI 00 Grease under Boundary Lubrication Conditions

NLGI 00 greases are often used to lubricate gears running at low pitch line velocities, such as, for example, in large open gear drives. At low pitch line velocities, sliding wear, which under these operating conditions is referred to as slow speed wear, is often the limiting factor to gear lifetime. A thorough knowledge of the effect of different grease components on the wear behavior is therefore important when selecting a grease to effectively reduce gear wear in a given gear drive. In order to systematically investigate and analyze the influence of different grease components on the slow-speed wear behavior of case-carburized gears, systematic gear tests using the Gear Research Center's (FZG) back-to-back gear test rig were conducted. Primarily, the focus of the experimental investigations is on the influence of the base oil viscosity and type, the additive type, and also the type of soap thickener on the gear wear behavior at low pitch line velocities. To experimentally determine the influence of these different grease components on the wear behavior of case-carburized gears, a modified, more stringent wear test, based on the standard DGMK slow-speed wear test for gear oils, was developed. Different NLGI 00 greases with base oil viscosities between ν₄₀ = 70 and 1,200 mm²/s were investigated.

Base oil type and base oil viscosity were shown to have only a minor effect on the wear behavior under boundary lubrication conditions. On the other hand, the thickener type and especially the additive type play an important role in determining the wear behavior.     

Characterisation of wear debris from UHMWPE on zirconia ceramic, metal-on-metal and alumina ceramic-on-ceramic hip prostheses generated in a physiological anatomical hip joint simulator

There is currently much interest in the characterisation of wear debris from different types of artificial hip joints. There have been numerous studies on the wear of UHMWPE in hip joint simulators, but relatively few studies on the wear of alternative materials such as metal-on-metal (MOM) and ceramic-on-ceramic (COC). The aim of this study was to compare the wear volumes and wear debris generated from zirconia ceramic-on-UHMWPE, MOM and COC hip joints under identical conditions in the same hip joint simulator.

All prostheses showed an initial higher ‘bedding in’ wear rate, which was followed by a lower steady state wear rate. The zirconia ceramic-on UHMWPE prostheses showed the highest wear rates (31±4.0 mm³/million cycles), followed by the MOM (1.23±0.5 mm/million cycles), with the COC prostheses showing significantly (P<0.01) lower wear rates at 0.05±0.02 mm³/million cycles. The mode (±95% confidence limits) of the size distribution of the UHMWPE wear debris was 300±200, 30±2.25 nm for the metal particles, and 9±0.5 nm for the ceramic wear particles. The UHMWPE particles were significantly larger (P<0.05) than the metal and ceramic wear particles, and the metal particles were significantly larger (P<0.05) than the ceramic wear particles. A variety of morphologies and sizes were observed for the UHMWPE wear particles, including submicrometer granules and large flakes in excess of 50 μm. However, the wear particles generated in both the MOM and COC articulations were very uniform in size and oval or round in shape.

This investigation has demonstrated substantial differences in volumetric wear. The in vitro wear rates for the zirconia-on-UHMWPE and MOM are comparable with clinical studies and the UHMWPE and metal wear particles were similar to the wear debris isolated from retrieved tissues. However, the alumina/alumina wear rate was lower than some clinical retrieval studies, and the severe wear patterns and micrometer-sized particles described in vivo were not reproduced here.

This study revealed significant differences in the wear volumes and particle sizes from the three different prostheses. In addition, this study has shown that the alternative bearing materials such as MOM and COC may offer a considerable advantage over the more traditional articulations which utilise UHMWPE as a bearing material, both in terms of wear volume and osteolytic potential.     

Simulating sliding wear with finite element method

Wear of components is often a critical factor influencing the product service life. Wear prediction is therefore an important part of engineering. The wear simulation approach with commercial finite element (FE) software ANSYS is presented in this paper. A modelling and simulation procedure is proposed and used with the linear wear law and the Euler integration scheme. Good care, however, must be taken to assure model validity and numerical solution convergence. A spherical pin-on-disc unlubricated steel contact was analysed both experimentally and with FEM, and the Lim and Ashby wear map was used to identify the wear mechanism. It was shown that the FEA wear simulation results of a given geometry and loading can be treated on the basis of wear coefficient−sliding distance change equivalence. The finite element software ANSYS is well suited for the solving of contact problems as well as the wear simulation. The actual scatter of the wear coefficient being within the limits of ±40–60% led to considerable deviation of wear simulation results. These results must therefore be evaluated on a relative scale to compare different design options.     

Wear Behavior of Aluminum Alloys at Slow Sliding Speeds

The investigated slow sliding speeds presented in this work enable the understanding of the wear behavior on aluminum alloys and could possibly facilitate the completion of the previously proposed wear mechanism map for aluminum at this slow sliding speed range. Dry sliding block-on-ring wear tests were carried out on aluminum alloys, AA5754 (Al-Mg), AA6082 (Al-Mg-Si), and AA7075 (Al-Zn-Cu), at a very slow sliding speed range (<0.01 m/s). A bearing steel ring of AISI 52100 was used as the counterbody. Tests were performed at varying contact pressures, 20, 100, and 140 MPa, and sliding speeds ranging from 0.001 to 1.5 m/s. The wear tracks and debris collected were examined by scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and X-ray diffraction (XRD), with the aim of analyzing their morphology and composition. At relatively slow sliding speeds (>0.01 m/s), the specimens exhibited a wear process placed at the mild wear regime, characterized by oxidation and delamination mechanisms of both the aluminum specimen and the steel ring. However, at very slow speed range (<0.01 m/s), an increase in the wear rate and the friction coefficient is observed for all of the aluminum alloys, thus suggesting that an alternative wear mechanism could be taking place.     

Wear particle analysis—utilization of quantitative computer image analysis: A review

This paper provides a general overview of developments and progress in quantitative computer image analysis as applied to wear particle identification/classification technology, over the last two decades. Since many technical disciplines are involved in this ‘infant-stage’ technical area, an attempt is made to put into perspective mechanical failure prediction/diagnosis and prevention through quantitative wear particle morphological analysis. The problems experienced with applying conventional wear particle analysis methods in machinery condition monitoring, notably the employment of wear debris morphological diagnostic systems, revealed that it is not prudent to rely solely on human interpretation in the analysis of ‘filtergram’ slides. This has highlighted the need for improving the provision of ‘intelligent’ objective methods for performing this type of analysis. In this paper, some of the developments reported in the literature relating to progress made with wear particle image analysis are reported and examined as a basis for establishing improved methods of diagnostic analysis.