【摘要】 介绍用 2万Hz超声波振动疲劳试验机对两种铁的高周 (大于 10 6 周 )摩擦疲劳强度进行研究。结果发现 ,这两种材料在高周到超高周区间 ,疲劳强度随材料寿命的加大呈明显减小 ,即S -N曲线呈明显下降趋势。这一结果与传统的假说完全不同。高周疲劳强度曲线使用低周疲劳强度的延长线比水平线假设更为恰当。借助于电子显微镜对试件断面作了观察及对引起疲劳破坏起始处进行了化学分析 ,对高强度钢的高周摩擦疲劳损坏机理作了探讨。更多还原

【Abstract】 An attempt has been made to characterize hi cycle(>10 6 cycles)fretting fatigue behavior of two kind of iron by means of an ultrasonic frequency of 20kHz fatigue test and analytical techniques.The experimental results show that the fatigue endurance stress continues to decrease with increasing number of cycles between 10 6 and 10 10 cycles.This result is much different from conventional hypothesis.The extension line of low cycle fatigue strength can be used as fatigue strength of hi cycle in stead of horizontal assumption.Observations of fracture section were made by using Scanning Electron Microscopy (SEM) and chemical analysis were made by special instrument.The fretting fatigue rupture mechanism of hi cycle of high strength steel is discussed.更多还原