钢结构的主要破坏形式之一为疲劳破坏,这类破坏往往伴随着钢材的突然断裂;目前针对Q690D高强钢材的疲劳性能研究还比较缺乏。为了得到Q690D高强钢的疲劳特性曲线,本研究开展了Q690D高强钢的高周疲劳试验,根据试验的结果拟合出Q690D高强...钢结构的主要破坏形式之一为疲劳破坏,这类破坏往往伴随着钢材的突然断裂;目前针对Q690D高强钢材的疲劳性能研究还比较缺乏。为了得到Q690D高强钢的疲劳特性曲线,本研究开展了Q690D高强钢的高周疲劳试验,根据试验的结果拟合出Q690D高强钢的应力-寿命(S-N)疲劳曲线,并与规范疲劳公式和其他强度等级钢材已有的疲劳试验曲线进行对比。试验结果表明:Q690D高强钢的疲劳性能远高于普通钢,且比美国钢结构规范(ANSI/AISC 360-10)和欧洲钢结构规范(BS EN 1993-1-9)的计算值要大,说明Q690D高强钢的疲劳性能比较优越,规范计算值偏保守;钢材的疲劳曲线与其屈服强度高度相关,且离散性很强。展开更多
The fatigue life of numerous aerospace,locomotive,automotive and biomedical structures may go beyond 10~8 cycles.Determination of long life fatigue behavior becomes extremely important for better understanding and des...The fatigue life of numerous aerospace,locomotive,automotive and biomedical structures may go beyond 10~8 cycles.Determination of long life fatigue behavior becomes extremely important for better understanding and design of the components and structures.Initially,before the invention of ultrasonic fatigue testing,most of the engineering materials were supposed to exhibit fatigue life up to 10~7 cycles or less.This paper reviews current understanding of some fundamental aspects on the development of accelerated fatigue testing method and its application in ultra-high cycle fatigue,crack initiation and growth mechanisms of internal fracture,S-N diagram,fatigue limit and life prediction, etc.展开更多
A method and procedure of high cycle fatigue life prediction for helicopter transmission system tail gearbox casing is presented, including fatigue test load, three parameters S-N curve, reduction factor and cumulativ...A method and procedure of high cycle fatigue life prediction for helicopter transmission system tail gearbox casing is presented, including fatigue test load, three parameters S-N curve, reduction factor and cumulative damage law. According to the fatigue test results, the design load spectrum and the three parameters S-N curve, a fatigue life prediction of the tail gearbox casing of a helicopter is performed as an example.展开更多
文摘钢结构的主要破坏形式之一为疲劳破坏,这类破坏往往伴随着钢材的突然断裂;目前针对Q690D高强钢材的疲劳性能研究还比较缺乏。为了得到Q690D高强钢的疲劳特性曲线,本研究开展了Q690D高强钢的高周疲劳试验,根据试验的结果拟合出Q690D高强钢的应力-寿命(S-N)疲劳曲线,并与规范疲劳公式和其他强度等级钢材已有的疲劳试验曲线进行对比。试验结果表明:Q690D高强钢的疲劳性能远高于普通钢,且比美国钢结构规范(ANSI/AISC 360-10)和欧洲钢结构规范(BS EN 1993-1-9)的计算值要大,说明Q690D高强钢的疲劳性能比较优越,规范计算值偏保守;钢材的疲劳曲线与其屈服强度高度相关,且离散性很强。
基金supported by the National Natural Science Foundation of China(10925211)the Program for Changjiang Scholars and Innovative Research Team (IRT1027)
文摘The fatigue life of numerous aerospace,locomotive,automotive and biomedical structures may go beyond 10~8 cycles.Determination of long life fatigue behavior becomes extremely important for better understanding and design of the components and structures.Initially,before the invention of ultrasonic fatigue testing,most of the engineering materials were supposed to exhibit fatigue life up to 10~7 cycles or less.This paper reviews current understanding of some fundamental aspects on the development of accelerated fatigue testing method and its application in ultra-high cycle fatigue,crack initiation and growth mechanisms of internal fracture,S-N diagram,fatigue limit and life prediction, etc.
文摘A method and procedure of high cycle fatigue life prediction for helicopter transmission system tail gearbox casing is presented, including fatigue test load, three parameters S-N curve, reduction factor and cumulative damage law. According to the fatigue test results, the design load spectrum and the three parameters S-N curve, a fatigue life prediction of the tail gearbox casing of a helicopter is performed as an example.
