基于扫描电镜原位高温疲劳测试方法研究

基于扫描电镜原位高温疲劳测试方法研究

周建力，任潇一，张宜旭，王 晋，张跃飞^*，张 泽

（1.北京工业大学固体微结构与性能研究所，北京100124；2.浙江大学材料科学与工程学院，浙江杭州310027）

摘  要 本文基于自主研发的扫描电子显微镜原位高温拉伸平台，测试样品高温疲劳性能。通过控制恒定应力加载，设计拉-拉疲劳实验，实时观察到纳米尺度疲劳微裂纹萌生扩展过程的微观结构演变过程，得到了高分辨、高放大倍数的实时序列SEM像，成功实现1000℃高温原位疲劳测试，对于研究纳米尺寸结构材料的高温疲劳失效微观机制有重要意义。

关键词 镍基单晶高温合金；原位扫描电镜；高温疲劳；微裂纹

中图分类号：TG14；TG115.21⁺5.3  文献标识码：A   doi:10.3969/j.issn.1000-6281.2021.03.001

Research on in situ high temperature fatigue test method based on scanning electron microscope

ZHOU Jian-li¹，REN Xiao-yi¹，ZHANG Yi-xu¹，WANG Jin²，ZHANG Yue-fei^1*，ZHANG Ze²

 (1. Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing100124; 2. School of Materials Science and Engineering, Zhejiang University, Hangzhou Zhejiang 310027，China)

Abstract  In recent years, the research on the initiation and propagation of fatigue microcracks mainly focuses on the in-situ fatigue tests under 800℃ in SEM. Few studies have been conducted on the initiation and propagation of nanoscale fatigue microcracks for nickel-based single crystal materials with nanoscale structure near the high temperature service condition (1050℃). In this paper, a high temperature in-situ SEM fatigue test method has been proposed. The microstructure evolution process of the initiation and propagation of nano-sized fatigue microcracks was observed in real time by conducting the fatigue test under constant stress loading. In the experiment, high-quality and magnification-scanning electron microscope sequence images were captured, breaking the challenge of in-situ fatigue test with the temperature of 1000℃.

Keywords  nickel-based single crystal superalloy；in situSEM；high temperature fatigue；microcracks

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