The Simulation of Stress Measurement of Conductor Materials with Eddy Current Thermography
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摘要: 当导体表面或内部存在应力集中区域时，该区域的材料参数如电导率、热导率等会发生相应改变。电导率及热导率是涡流热成像（ECT）检测过程中感应加热与热传导阶段的重要影响因素。在获得电导率和热导率等参数对ECT检测结果影响规律的前提下，可以通过ECT检测导体材料的应力状态。在COMSOL MULTIPHYSICS多物理仿真平台上采用数值仿真分析的方法，研究了导体材料的电导率、热导率大小及应力层厚度对被测试件表面温度的影响规律，获得了应力值与温度变化的映射关系。结果表明：在一定范围内，导体应力值、应力层厚度与其表面温度均近似为线性关系。导体拉应力值及应力层厚度越大，应力层的温度越高；压应力值及应力层厚度越大，应力层的温度越低。仿真结果可为后续开展涡流热成像定量检测导体材料的应力提供理论参考。
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关键词:
- 应力检测 /
- 涡流热成像检测(ECT) /
- 导体材料 /
- 电导率 /
- 热导率
Abstract: Stress concentration area on the surface or inside the conductivity material will change its electromagnetic and heat transfer parameters accordingly, such as the electrical conductivity, thermal conductivity and so on. The electrical conductivity and thermal conductivity play important role in the process of induction heating and heat propagation process of eddy current thermography (ECT) testing. If the influence of electrical conductivity and thermal conductivity on the testing result of ECT is known, the stress state of conductor material can be measured with ECT by extracting features of the temperature distribution or temperature rise from the IR images or image sequence. In this paper, the effects of electrical conductivity, thermal conductivity and stress layer thickness on the surface temperature of the specimen were investigated by the means of numerical simulation with COMSOL MULTIPHYSICS. The relationship between stress value, stress layer thickness and temperature variation was presented. The results show that the relationship between the stress and its thickness of the specimen and its surface temperature is approximately linear in a certain range. The higher the tensile stress and the bigger its thickness are, the higher the stress layer temperature is, and the higher the compressive stress and the bigger its thickness are, the lower the stress layer temperature is. The simulation results presented in this paper could be a theoretical reference for the further study on stress measurement of conductivity material by using ECT. -
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[1] WEEKES B, ALMOND D P, CAWLEY P, et al. Eddy-current induced thermography-probability of detection study of small fatigue cracks in steel, titanium and nickel-based superalloy[J]. Ndt & E International,2012, 49:47-56.
[2] CHENG L, TIAN G Y. Surface crack detection for carbon fiber reinforced plastic (CFRP) materials using pulsed eddy current thermography[J].IEEE Sensors Journal, 2011,11(12):3261-3268.
[3] 闫会朋,杨正伟,田干,等. 基于涡流热成像的铁磁材料近表面微裂纹检测[J]. 红外与激光工程, 2017,46(3):238-243. [4] CHENG Liang, HE Yunze, PAUL J, et al. Pulsed eddy current thermography for corrosion characterisation[J]. International Journal of Applied Electromagnetics & Mechanics, 2012, 39(1):269-276.
[5] 胡德洲,左宪章,李伟,等. 钢板表面腐蚀的脉冲涡流热成像检测研究[J]. 激光与红外, 2015,45(2):144-149. [6] 闫贝,李勇,李达. 金属亚表面腐蚀缺陷的脉冲调制涡流磁场梯度成像[J]. 无损检测, 2016, 38(4):10-14. [7] 刘兴乐,刘志平,黎玄. 基于脉冲涡流热成像的金属结构焊缝表面裂纹识别方法[J]. 中国机械工程, 2016, 27(14):1925-1931. [8] CHENG Y H, BAI L B, YANG F, et al. Stainless steel weld defect detection using eddy current pulsed thermography[C]//2015 IEEE International Conference on Applied Superconductivity and Electromagnetic Devices (ASEMD). Shanghai:[s.n.], 2016:559-560.
[9] JIANG Lei, LIU Zhiping, LIU Xingle, et al. Research on detecting weld cracks by eddy current thermography[J]. Journal of Wuhan University of Technology, 2015,1:874-880.
[10] PENG J P, TIAN G Y, WANG L, et al. Investigation into eddy current pulsed thermography for rolling contact fatigue detection and charac-terization[J]. Ndt & E International, 2015, 74(6):72-80.
[11] LIU J, REN W, TIAN G Y, et al. Early contact fatigue evaluation of gear using eddy current pulsed thermography[C]//2014 IEEE Far East Forum on Nondestructive Evaluation/Testing. Chengdu:[s.n.], 2014:208-212.
[12] LIU J, REN W W, TIAN G Y, et al. Nondestructive evaluation of early contact fatigue using eddy current pulsed thermography[J]. IEEE Sensors Journal, 2015, 15(8):4409-4419.
[13] 刘录叶,邓淑文,杨随先. 残余应力涡流热成像无损检测技术及应用[J]. 无损检测, 2018, 40(10):5-9. [14] BAI L B, TIAN G Y. Stress measurement using pulsed eddy current thermography[C]//2014 IEEE Far East Forum on Nondestructive Evaluation/Testing. Chengdu:[s.n.], 2014:208-212.
[15] 周小东.基于脉冲涡流热成像的应力检测技术研究[D]. 成都:电子科技大学, 2016. [16] 雷庆,黎玄,王亚辉. 钢结构应力的脉冲涡流热成像检测方法[J]. 机械设计与研究, 2017(4):111-115. [17] 潘孟春,何泽,陈棣湘. 涡流热成像检测技术[M]. 北京:国防工业出版社, 2013. [18] 邹宇.金属构件非均匀分布应力的涡流无损检测方法研究[D]. 成都:电子科技大学, 2016. [19] 任吉林. 涡流检测[M]. 北京:机械工业出版社,2013.
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