疲劳

Aimed at the crankshaft fatigue of certain typed 4 cylindered internal combustion engine this paper established the dynamics model of piston-shaft system and carried out simulation.A...

文中针对某型号4缸内燃机曲轴疲劳，建立了活塞-轴系动力学模型并进行仿真，然后把仿真结果转化为时间载荷传递到曲轴的有限元计算模型中，最后对该有限元模型进行疲劳仿真，从而获得整个曲轴的疲劳寿命计算结果。

The results under the oil lubricate friction conditions were similar with those under the dry friction conditions. The wear mechanism of 3Cr13 matrix alloy was micro-cutting and distorting wear. For the composites with a low fraction of TiC particle, distorting wear dominated and cutting was partly operating. For the composites with a high fraction of TiC particle, stress fatigue wear and wear of hard phase decohesion has occurred, but the main wear mechanism was still distorting wear. When the wear experiments were performed under the oil lubricate friction conditions, the main wear mechanism has became to abrasive wear and fatigue wear for the composites with the low TiC fraction, and fatigue wear would be to dominate for the composites with the high TiC fraction. There were similar wear mechanisms in H13 and 1Cr18Ni9 matrix composites.

在干摩擦条件下，3Cr13基体合金的磨损机理为显微切削和变形磨损；低体积分数的复合材料磨损机制以变形磨损为主，兼有少量的切削磨损机制；高体积分数的复合材料磨损机制以变形磨损为主，兼有应力疲劳磨损和脆性相剥落磨损；在油润滑摩擦条件下，3Cr13基体合金的磨损以磨粒磨损为主；低体积分数的复合材料磨损为磨粒磨损和疲劳磨损；高体积分数的复合材料磨损以疲劳磨损为主。H13、1Cr18Ni9基体及其复合材料的磨损机制类似于3Cr13基体及其相同体积分数的复合材料。

On the base of fatigue loading spectrum achievements, combining the characteristics of large-span grid structure with hanging cranes and the using-requirement on fatigue loading spectrum of grid structure with hanging cranes, this paper has firstly put forward the theoretic method for constructing fatigue loading spectrum of grid structure with hanging cranes, organized the relevantprogram--GJFLS. and elementally established the program loadingspectrum .

在继承疲劳载荷谱已有成果的基础上，本文结合网架设置悬挂吊车的特点以及网架疲劳载荷谱的使用要求，首次提出了网架疲劳载荷谱编制的理论方法，并编制了相应的程序，初步建立了网架程序载荷谱。

Abstract］ objective to investigate the clinical effect of esculin and digitalisglycosides eye drops for asthenopia after lasik.methods 100 eyes of 50 cases were given esculin and digitalisglycosides eye drops to treat asthenopia,compared with matched control subjects（100 eyes） of asthenopia and amplitude of accommodation.results in one and two weeks after lasik, esculin and digitalisglycosides eye drops were more effective compared with matched control subjects.conclusion esculin and digitalisglycosides eye drops are effective and safe for treatment of asthenopia after lasik.

目的 观察七叶洋地黄双苷滴眼液治疗lasik术后视疲劳的疗效。方法运用七叶洋地黄双苷滴眼液治疗lasik术后病人50例100眼，以视疲劳的自觉症状及眼调节幅度为观察指标，与对照组进行对比。结果术后1周及2周时七叶洋地黄双苷滴眼液治疗组较对照组主观症状及眼调节幅度有明显改善。结论七叶洋地黄双苷滴眼液治疗lasik术后视疲劳安全有效。

In this paper, the relationship between the fatigue crack front straightness S t and fatigue loading ratio f were explored.

通过实验，研究了疲劳裂纹前沿平直度 St与疲劳载荷比 f 之间的关系，发现两者高度正相关，为预制具有平直裂纹前沿的疲劳裂纹提供了有效的途径和方

Experiments are conducted to determine the gigacycle fatigue behavior of nodular cast iron GS51 by ultrasonic fatigue test system.

应用超声疲劳试验技术，完成了20kHz频率下(R=-1，R=0 1)的疲劳试验，获得球墨铸铁GS51在亿周次范围内的疲劳性能。

Written by pioneers in the study and analysis of very high cycle fatigue, Gigacycle Fatigue in Mechanical Practice compiles the most recent findings on gigacycle fatigue phenomena, focusing on improving the reliability and performance of key engine and machine components.

以开发者写在书房里和高循环疲劳的的分析，在机械实践过程中的Gigacycle 疲劳在gigacycle疲劳现象上编辑最新近的结论，集中于改进关键发动机的可靠性和性能和机器零部件。

Experiments were conducted to determine the gigacycle fatigue behavior of cast Aluminum AS5U3G-Y35 by ultrasonic fatigue test system.

应用20kHz频率下的超声疲劳设备完成亿周次疲劳试验，获得铸铝AS5U3G-Y35超高周疲劳特性。

The test equipment, installation and test principle of gigacycle friction fatigue were introduced in this paper,On the basis of the fatigue test apparatus of 20 KHz ultrasonic vibration,the frequency value,the dimension calculation formulas and the specific shape of the specimen were given.

介绍了高周摩擦疲劳试验设备、装置及试验原理根据 2 0 0 0 0Hz超声波震动疲劳试验机的要求，给出了试件的频率值、尺寸计算、公式和具体形状；最后，给出了摩擦力、应力与位移的表达形式和疲劳寿命的记录方

The Parabola Hypothesis corrected by the authors. The authors have used this method on computer to get the bending fatigue test data of carburized and quenched gears and the fatigue limiting stress distribution. Furthermore, the...

然后对渗碳淬火钢齿轮的弯曲疲劳试验数据用JFKC法进行计算，得到了它的疲劳极限应力分布，并对比其相应的成组试验法测定的疲劳极限应力分布进行了分析和讨论。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了