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1.
通过分析现有的车轮弯曲疲劳试验机的失效检测方法,并遵照相关试验要求,完成了基于激光位移传感器的车轮弯曲疲劳试验加载轴偏移量检测系统的设计.该系统用于试验中加载轴的偏移量的实时监测,进而达到车轮失效时试验机自动卸载的目的.  相似文献   

2.
利用Abaqus对汽车车轮进行结构分析,基于有限元分析结果通过fe-safe软件对车轮耐久性进行预测,阐述分析软件在模拟车轮疲劳寿命台架试验方面的应用.  相似文献   

3.
为提高车轮设计质量,应用有限元方法,根据国家标准,对某型车铝合金车轮进行疲劳寿命分析,并结合试验设计、近似建模技术及基于蒙特卡罗模拟技术的6σ可靠性优化设计理念,从提高车轮寿命、减轻重量角度进行车轮优化设计。结果表明,轮辐上开孔能够有效引导车轮受载情况下的应力分布,改善疲劳载荷的循环特性,从而有效地提高车轮疲劳寿命。通过对车轮进行确定性优化和基于6σ的可靠性优化的对比,分析了设计变量波动对产品设计质量的影响,结果表明,可靠性优化明显优于确定性优化,具有较高的工程实用价值。  相似文献   

4.
针对现有疲劳寿命试验机存在异常停机、无远程监控和试验数据保存不完整等问题,对其基于LabVIEW的测控系统进行了改进,增加了智能停机、远程监控、数据分块保存等功能模块,并对改进后的测控系统进行了基于滚动轴承磷化处理项目的试验测试,试验结果表明:改进后的测控系统解决了上述问题,在实现其基本功能的同时提高了试验效率、扩展了试验机功能,提高了试验机的测控性能,为滚动接触疲劳寿命的研究提供了有力的技术支持。  相似文献   

5.
测控系统模块化设计是现代控制系统设计的一种发展趋势,以电液式万能试验机的测控系统为例,介绍了微机测控系统的模块化设计思想,通过对电液式万能试验机的微机测试系统进行改进,试验机的试验速度,试验精度和先进程度都得到了提高,实现了试验过程全自动化。  相似文献   

6.
我们设计制造了一台单板机控制的程序疲劳试验机,经调试,效果满意。试验机基本可分电液伺服、电控、单板机三大部分。这里仅就单板机的作用和硬件、软件的设计作一简单介绍。一、单板机的用途一般的疲劳试验机,为了实现试验过程的程序控制,或是采用继电器逻辑,或是采用顺序控制器。这些方案的主要缺点是试验程序改变麻烦,且为有限步,此外还需要配备信号发生器。因此,我们决定采用单板机来完成以上功能,目的是向操作人员提供简便、直观的操作方法。  相似文献   

7.
对流传热系数的准确计算对研究机车车轮温度场和应力场及其疲劳寿命预测有重要意义.针对HXD2机车车轮踏面制动过程,建立车轮及其绕流流场计算模型,应用CFD方法通过仿真得到机车车轮在不同运行速度下的对流传热系数.结果表明:由于车轮自身旋转,车轮表面不同位置处的对流传热系数不同;车轮上半迎风面的对流传热系数较大,下半迎风面较小,且都大于背风面数值.计算结果为研究机车车轮对流传热、蠕滑和制动等传热过程提供参考.  相似文献   

8.
为分析某牵引车在比利时路上的车架疲劳,建立该牵引车整车多体动力学模型。将试验测得的车轮六分力加载到模型中进行仿真分析,并与试验结果对比,验证模型的可信性。提取多体动力学仿真结果中的车架载荷历程,基于模态应力恢复理论对车架进行疲劳分析,预测车架疲劳寿命。仿真结果表明该分析方法可作为车架疲劳分析的有效手段。  相似文献   

9.
在当前试验机领域,动态控制一直是试验机测控系统亟待解决的一个难点,现有的测控系统,难以做到高频率下的高精度控制,难以满足材料试验行业的动态试验需求.针对这一难点,设计了基于MSP430的沥青疲劳试验机测控系统.系统以16位混合信号处理器MSP430F149为核心,实现频率0.1~10 Hz可调,参数在线配置等功能.应用结果表明,该测量控制系统测量准确、控制精度高.  相似文献   

10.
叙述了如何将多线程技术应用到疲劳试验机控制及远程监测系统中,以实现循环采集和随时传送实时数据的过程,利用线程工作的特点,设计了相应的线程来完成系统软件部分.通过线程技术的使用,试验系统可在循环采集数据的同时接受远程传来的任何信息,并实时地将本机的数据传给远程计算机.多线程技术使得计算机同时执行多个任务成为可能,在实践中得到了广泛的应用.文章还分析了使用线程的弊端,指出线程的使用是要根据具体试验来确定的.  相似文献   

11.
Quasi-static bending and fatigue tests of single-crystal silicon microelements fabricated by photoetching were performed. The microelements were subjected to simple bending and three-point bending with two-support roll length of 1.5 mm. The tests were conducted by using a specially designed electromagnetic actuator based testing machine (load range: 0.1 mN–5 N, accuracy: 0.02 mN), which enables mechanical testing including fatigue of microelements. Mechanical testing including fatigue of microelements could be performed with sufficient precision. Single-crystal silicon microelements deformed elastically until final catastrophic failure, showing a brittle nature. The influence of specimen size on quasi-static fracture behavior was investigated: fracture strength increased with a decrease in sample width, and the maximum fracture strength reached 7.7 GPa. The influence of water on fatigue strength was discussed. The fracture surface and sample surface were examined using an atomic force microscope. Nanoscopic damage during testing was evaluated, and the fracture mechanisms were discussed. Received 20 October 1997/Accepted 5 January 1998  相似文献   

12.
为了分析新型材料航空发动机轴承的失效原因并提高轴承的使用寿命和可靠性,研制了一台能够模拟航空发动机工况的轴承疲劳试验机,设计了基于西门子S7-1500PLC的远程测控系统.测控系统通过PLC控制模块、驱动器和变频器等,实现了动力系统、润滑系统和加载系统的控制和试验载荷谱线的自动运行.试验主参数信号通过高速高性能模拟量A/D模块进行采集,并通过以太网传输至上位机.上位机软件对数据进行实时处理、存储和绘制曲线.通过试验验证,所设计的轴承试验机测控系统设计合理、运行可靠,为航空发动机轴承寿命研究和性能试验提供了基础平台和数据支撑.  相似文献   

13.
The surface temperature behavior of a steel specimen under bending fatigue is exactly divided into three stages: an initial temperature increase stage, a constant temperature stage and an abrupt temperature increase stage at the end of which the specimen fails. To obtain the endurance state of the specimen we use its thermal images (TIs). By applying artificial neural networks (ANNs) and other operations to these TIs we obtain spots with maximal, approximately medium and minimal temperatures. Then by using these temperatures we analytically obtain the temperatures all of spots of the specimen and localize the regions consisting of spots of relatively high temperatures. We consider such a region as one to be cracked firstly. This approach allows us to handle only those spots that are of interest and to work in real-time even by using an infrared (IR) camera and a computer with average technical features. We are using the result obtained in this study for fatigue testing the steel materials and for sensing the pre-fatigue state of a specific part of a machine being worked in order to take preventive measures before it breaks down.  相似文献   

14.
Silicon will continue to be the critical structure material for micromechanical components for years to come so that reliability must be a key concern. Consequently, in order to ensure reliability design approaches must account for fatigue behavior. This work is aimed at studying the fatigue of single crystal silicon (SCS) thin films by a specially designed method. The films were tested using cantilever microbeam deflection with respect to the effect of loading conditions. To conduct a fatigue test under cyclic strain would be more realistic because many MEMS applications, such as micro-accelerometers and micro-filters, consist of beams vibrating in the same mode. A micro-force testing machine with a micro-probe and specially designed fixtures is used to contact and load the beams under the cyclic strain. Before the fatigue test, the failure strain f of beams in the flexural test is achieved as the testing criterion. In fatigue testing, various percentages of failure strain f, two times of the strain amplitude, are adopted. First of all, fatigue strain–life cycle (S/N) curve is achieved. Further, the curve of fatigue force detected on the SCS versus fatigue life is measured. SEM is also employed to observe the fracture modes of films under fatigue. Based on the SEM observation and force/life curve, the failure mechanism of the fatigued SCS films under the cyclic strain is proposed. This provides a viable method to evaluate the reliability of the SCS.  相似文献   

15.
An automated procedure is developed to determine the influence of a crack detected in a structural element subjected to cyclic combined axial and bending loadings with constant amplitude. A theoretical formulation for fatigue crack growth analysis is presented and the results obtained are compared with the experimental data of the Wöhler curves. The critical crack configurations for which the fatigue failure occurs after a given number of loading cycles can be obtained from the above-mentioned comparison. Finally, an example is shown in order to illustrate the use of a computer program, which translates the proposed procedure.  相似文献   

16.
根据电缆折弯测试的实际需要,研制出用于电缆折弯的测试机,介绍了该测试机的设计指标、工作原理和具体实现过程。通过测试机的使用,提高了测试的有效性和稳定性。  相似文献   

17.
To establish a bridge between grinding tool parameters and loaded tooth fatigue life, an innovative data-driven root flank bending fatigue life forecasting and optimization via Top-Rem tool parameters was proposed for grinding spiral bevel gears. The recent machine settings modification is extended into grinding Top-Rem tool parameters modification in case that geometric accuracy and root bending fatigue life are integrated into a collaborative optimization. The proposed Top-Rem modification includes three key steps: (I) arc-shaped blade, (II) top part, and (III) top fillet part. Then, while root bending stress is determined by using finite element method (FEM)-based simulated loaded tooth contact analysis (SLTCA), data-driven fatigue life forecasting is developed by correlating with the multiaxial fatigue damage model based assessment. Moreover, data-driven bending fatigue life optimization model is established by using Top-Rem tool parameters modification, where the important constraints in target flank determination includes: (i) root overcutting, (ii) geometric accuracy, and, (iii) fatigue life. For high accuracy and efficiency, two different strategies are proposed: (i) the different parameters modification types; and, (ii) sensitivity analysis of grinding Top-Rem tool parameters. Finally, proposed method can verify that bending fatigue life can be significantly improved by modifying the key Top-Rem tool parameters in early stage of the whole life product development for spiral bevel gears.  相似文献   

18.
以T形焊接接头为研究对象,将可能发生疲劳破坏的焊趾截面和焊喉截面的节点力转换为相对于中面焊线的等效节点力和弯矩,并利用平衡等效原理转化为线力和线弯矩,基于材料力学公式求出截面的结构应力,解决应力对网格尺寸敏感的难题。从焊缝疲劳破坏的机理出发,基于Paris断裂力学公式推导以等效结构应力为变量的一条主S-N曲线,评估焊缝的疲劳寿命。分析结果发现:采用主S-N曲线法评估的寿命与试验值最接近且破坏位置准确,该主S N曲线法准确性较高。  相似文献   

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