超声疲劳狗骨平面试样设计与疲劳寿命实验研究  

Design of Ultrahigh Cycle Fatigue Sample with Planar Section and Experimental Verification Through Fatigue Life Testing

作　　者：舒力力 李岳刚 徐乾罡 张桢 Lili Shu;Yuegang Li;Qiangang Xu;Zhen Zhang(Department of Engineering Mechanics,School of Aerospace Engineering,Huazhong University of Science and Technology,Wuhan,430074;Hubei Key Laboratory of Engineering Structure Analysis and Safety Assessment,Huazhong University of Science and Technology,Wuhan,430074)

机构地区：[1]华中科技大学航空航天学院,工程力学系,武汉430074 [2]华中科技大学工程结构分析与安全评定湖北省重点实验室,武汉430074

出　　处：《固体力学学报》2024年第3期392-400,共9页Chinese Journal of Solid Mechanics

基　　金：国家科技重大专项(J2019-IV-0010-0078);国家自然科学基金项目(12172139)资助。

摘　　要：超声谐振技术是研究金属材料超高周长寿命疲劳性能的有效手段之一.超声疲劳试样通常需要独特的几何设计以满足共振的要求.常规疲劳试样如圆棒以及狗骨等不具备平面特征,在定量微观表征等方面存在困难.本文介绍了一种基于狗骨型拉压疲劳试样的带平面超声拉伸疲劳试样及其设计方法、疲劳测试方法.与传统超声疲劳试样设计不同的是,本文的狗骨平面试样具备平面试验段,具有利于定量微观表征的特征.本文以GH4169镍基合金为例,开展狗骨平面疲劳试样设计.通过超声疲劳试验结果表明,本文提出的基于理论解和数值方法的狗骨平面试件能在20 kHz产生共振,并且测得应力数据基本与现有材料S-N曲线相符.本文方法为超声疲劳试样设计与超高周疲劳的微观变形机制研究提供了新思路.Ultrasonic resonance technology is the most effective method for studying the ultra-high cycle fatigue properties of metal materials.Ultrasonic fatigue specimens typically need a distinctive geometric design to fulfill the resonance requirements.Traditional specimens,such as round rod and dog bone,do not have planar characteristics,which makes microscopic characterization difficult.This paper presents an ultra-high-cycle tensile fatigue specimen with a featured plane based on a traditional dog-bone tensile-compression specimen design.Different from the traditional specimen design,the dog-bone specimen herein has a flat observation area,which is readily to implement microscopic characterization.This paper takes GH4169 nickel-based alloy as an example to verify the proposed plane featured dog-bone fatigue specimen design.As expected,the ultrasonic fatigue test results show that the proposed dog-bone plane specimen can resonate at 20kHz.The measured fatigue life data is basically consistent with available S-N results in the literature.The proposed method provides new ideas for the design of ultra-high cycle fatigue specimens,as well as helps in the study of micro-deformation mechanisms of ultra-high cycle fatigue.

关 键 词：超高周疲劳 超声振动 狗骨 平面试样 

分 类 号：TG115.57[金属学及工艺—物理冶金]