作者：李思宽¹, 谈建平¹, 张坤¹, 史浩¹, 刘利强¹, 庄法坤², 涂善东¹

作者单位：1. 华东理工大学机械与动力工程学院 承压系统与安全教育部重点实验室, 上海 200237;
2. 中国特种设备检测研究院, 北京 100029

关键词：蠕变;蠕变裂纹扩展;小试样;高通量;试验装置

摘要：

对于某些取样受限的结构，如在役构件、薄壁件、焊接接头、功能性梯度结构，无法采用传统试样测试获得高温蠕变及裂纹扩展性能，小试样测试方法使得此类构件的高温力学性能的获取成为可能。但现有小试样蠕变试验装置用途单一且存在试样氧化的问题，无法满足试验要求。本文设计一种基于小试样的材料蠕变及蠕变裂纹扩展性能测试装置，装置配备专用夹具和真空系统，可满足不同种类小试样真空环境下的高温试验，避免试样氧化，并可同时完成6个同类或不同类型小试样的蠕变和蠕变裂纹扩展试验。装置采用马弗炉对试样加热，最高试验温度可达1 200 ℃。采用光栅位移传感器测量小试样变形量，直流电位法测量裂纹长度，提高了变形测量精度。试验结果表明，该装置可以精确测量小试样位移和裂纹长度，用以研究材料蠕变及裂纹扩展性能。

Design of high-throughput creep and creep crack growth testing equipment based on small specimen techniques
LI Sikuan¹, TAN Jianping¹, ZHANG Kun¹, SHI Hao¹, LIU Liqiang¹, ZHUANG Fakun², TU Shandong¹
1. MOE Key Laboratory of Pressure Systems and Safety, School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai 200237, China;
2. China Special Equipment Inspection and Research Institute, Beijing 100029, China
Abstract: It is generally hard to obtain creep and creep crack growth properties using traditional specimens for certain sampling limited structures such as in-service structures, thin-walled structures, welded joints and structures with functional gradient materials. The recently developed small specimen testing technique makes it possible to obtain high temperature mechanical properties of such structures. However, the existing small specimen creep testing equipment cannot test different types of specimens at the same time and can hardly avoid problem of specimen oxidation. In this study, a high-throughput creep and creep crack growth testing equipment based on small specimen techniques is developed. The equipment uses different fixtures to fit different kinds of small specimens and can be vacuumed to prevent specimens from oxidizing. Creep and creep crack growth tests on six different or the same kinds of small specimens can be performed at the same time. The specimen is heated by a muffle furnace, and the maximum temperature is up to 1200℃. Grating displacement sensors and direct current electrical potential instrumentations are used to measure deformation and crack length of specimens, respectively. The testing results show that the equipment can accurately measure the displacement and crack length of small specimen to investigate the creep and crack growth properties of materials.
Keywords: creep;creep crack growth;small specimen;high-throughput;experiment equipment
2019, 45(12):83-89  收稿日期: 2019-02-14;收到修改稿日期: 2019-05-23
基金项目: 国家重点研发计划（2018YFC0808800）；国家自然科学基金（11472105，11502082）
作者简介: 李思宽(1994-),男,辽宁铁岭市人,硕士研究生,专业方向为高温试验装置设计
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