Hopkinson杆式冲击疲劳试验方法研究  

Method for experiment study on impact fatigue based on Hopkinson bar

作　　者：李泊立 赵思晗 刘圆梦 杨建辉 郭伟国[1] LI Boli;ZHAO Sihan;LIU Yuanmeng;YANG Jianhui;GUO Weiguo(School of Aeronautics,Northwestern Polytechnical University,Xi'an 710072,China)

机构地区：[1]西北工业大学航空学院,西安710072

出　　处：《振动与冲击》2023年第2期132-138,共7页Journal of Vibration and Shock

基　　金：国家自然科学基金(12072287,11872051)。

摘　　要：在民用与国防领域,装备或结构部件常常受到高加载率的重复冲击,即冲击疲劳问题。冲击疲劳试验装置是研究冲击疲劳问题的基础,该研究提出一种分离式Hopkinson杆式冲击疲劳试验方法。首先通过真空系统使撞击弹复位,在加载过程中通过弹性约束对入射杆进行限位,最后利用电动推杆使透射杆和试样复位,以上过程通过PLC控制器控制。这种方法操作简易,能通过在杆上的信号采集实现冲击波的连续实时显示,并能改变撞击体几何构形以产生不同形状(梯形波、三角波或半正弦波)和不同加载率(8×10^(5)~3×10^(6)MPa/s)的冲击加载波,加载频率范围在0~0.5 Hz。最后利用高强钢圆柱试样和含有工艺缺陷的增材制造316L不锈钢三点弯曲试样对试验方法进行了验证,证明该方法有效可靠。In both civilian and military fields, equipments or structural components are often subjected to repeated impacts with high loading rates, that is, the impact fatigue. The impact fatigue test device is the basis for studying the impact fatigue problem, therefore an impact fatigue test method based on the split Hopkinson bar was presented, where the impact projectile was reset by a vacuum system, the position of the incident bar was limited by elastic restraint during the loading process, and the transmission bar and the specimen were reset by an electric push bar. The above process was controlled by a PLC controller. Through signal acquisition on the bar, the continuous real-time display of waves was realized. The method is easy to operate and by changing the geometric configuration of the impact projectile, the loading wave can be produced with different wave configurations(trapezoidal wave, triangle wave and half sine wave) and different loading rates(8×10^(5)-3×10^(6) MPa/s). The loading frequency ranges from 0-0.5 Hz. Finally, the applicability of the method was demonstrated by the test results of high-strength steel cylindrical specimens and three-point-bending specimens manufactured by additive 316L stainless steel with process defects.

关 键 词：冲击疲劳 重复加载 HOPKINSON杆 三点弯曲试样 

分 类 号：O347.4[理学—固体力学]