宋星亮外文翻译.doc

毕业设计（外文翻译） 英文题目 Development of a Deflection Controlled Multlaxlal Fatigue Testing Maching 中文题目 偏心控制的多轴疲劳试验机设计 系 （院） 机电工程系 专 业 机械设计制造及其自动化 学生姓名 宋星亮 学 号 1214090422 指导教师 龙秀慧 职 称 讲师 二〇一六 年三月 Development of a Deflection Controlled Multlaxlal Fatigue Testing Maching This paper discusses the development of a multiaxial fatigue testig machine. The deflection controlled eccentric disk type testing machine produces mode I, mode II, or combination of both, of crack surface displacements on round or flat specimens. These loadings are necessary for research on complex multiaxial stresses which are common in engineering practice, such as crankshafts. This machine achieved the objective with very simple mechanisms (vector sum of two crank throws of eccentric disks yield bending moments; vector differences, twisting moments), but with more computation in setting the desired parameters. Bending data and torsion data produced by the machine were in good agreement with the data by a conventional fatigue testing machine. Multiaxial data produced by the machine were also in good agreement with the prediction by a well proved multiaxial fatigue theory. Applications of the multiaxial fatigue testing machine are described. Key Words：Multiaxial Fatigue, Bending, Torsion, Out-of-Phase, Deflection Controlled, Testing Machine, Discriminating Specimen 1.INTRODUCTION Most engineering components suffer multiaxial cyclic loadings. Fatigue crack initiation and propagation under multiaxial loadings show different behavior from those of uniaxial loading. Fatigue life prediction of structures or machine parts under multiaxial loadings is essential to their reliable design and failure prevention. Such prediction was often based on simple laboratory data generated under cyclic uniaxial lo