摘要
介绍用 2 0kHz超声波振动疲劳试验机对一组高强度钢 5 4SCV6的 2 9个试件的超高周 (1 0亿周 )疲劳强度研究结果 .研究发现 ,该种材料的高周直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 .这一结果与传统的假说认为该区间的疲劳强度为水平渐近线或为一定值完全不同 .并给出实际结果与传统假说间差别 .借助于电子显微镜对试件微观组织的观察及对引起疲劳破坏起始处进行化学分析 .对材料的高周及超高周疲劳机理作进一步研究发现低周疲劳破坏的原因是试件表面夹杂与空洞 ,高周疲劳破坏原因是构件内部夹杂与空洞 ,低周与高周过渡区间的破坏则是内部或表面的夹杂与空洞 .
An attempt has been made to characterize gigacycle (1010 cycles) fatigue behavior of high strength spring steel (54scv6) wire by means of an ultrasonic frequency of 20 KHz fatigue test and analytical techniques. The fatigue strength of the steel wires in Gigacycle cycles was determined at a load ratio R=-1. The experimental results show that fatigue rupture can occur and 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 different between conventional hypothesis and test result is showed. Observations of fracture section were made by using Scanning Electron Microscopy (SEM) and chemical analysis were made by special instrument. The fatigue rupture mechanism of gigacycle of high strength steel is discussed.
出处
《哈尔滨工业大学学报》
EI
CAS
CSCD
北大核心
2000年第1期82-85,共4页
Journal of Harbin Institute of Technology
