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1、第 44 卷第 8 期中国测试Vol.44 No.82018 年 8 月CHINA MEASUREMENT & TESTAugust, 2018doi:10.11857/j.issn.1674-5124.2018.08.006钢轨服役疲劳特性的非线性表面波检测研究陈选民1,陈峰2(1. 广州铁路职业技术学院轨道交通学院,广东广州 510430; 2. 中南大学交通运输工程学院,湖南长沙 410075)摘 要:该文利用非线性表面波检测方法对钢轨在不同服役年限后的疲劳特性进行评价,通过推导得到表面波相对非线性系数的测量表达式,选取服役期为0、1、2、5、10和20年的钢轨,采用楔块探头研
2、究非线性表面波在钢轨截面传播特性,以此分析表面波非线性系数的规律。实验结果显示服役初始阶段钢轨的非线性系数的变化很小,随着服役时间的增加钢轨非线性系数变化速率呈现增大的趋势;通过对钢轨微观组织分析,表明位错密度增加所导致的微裂纹是钢轨的非线性系数增大的重要原因。研究将为非线性超声检测钢轨服役疲劳损伤提供理论依据,对预防钢轨因疲劳导致的失效,保证钢轨的安全服役和铁路运行安全提供新的研究方向。关键词:钢轨检测; 非线性表面波; 服役年限; 疲劳损伤中图分类号:U216.3 文献标志码:A 文章编号:1674–5
3、124(2018)08–0032–05ExperimentalinvestigationofrailfatigueinserviceusingnonlinearsurfacewaveCHEN Xuanmin1, CHEN Feng2(1. College of Railway Transportation, Guangzhou Railway Polytechnic, Guangzhou 510430, China;2. School of Traffic and Transportation Engineering, Central South University, Changs
4、ha 410075, China)Abstract: The paper studied the rail fatigue characteristics with different service years by using nonlinearsurface waves, then derived the relative nonlinear surface wave parameter. It adopted angle beam wedgetransducers to measure the propagation of nonlinear surface waves in t
5、he cross section of rails with the serviceyears of 0, 1, 2, 5, 10, 15 and 20 respectively and analyzed the laws of nonlinear surface wave parameters. Theresults showed that, the change of the nonlinear parameter of rail at the initial stage of service was very small,and the nonlinear parameter of
6、 rail increased with the increase of service year. According to the metallographicanalysis, it was found that the main reason for the increase of nonlinear parameter was the micro-crack causedby the increase of dislocation density. This paper will provide theoretical basis for evaluation of the r
7、ail fatiguethrough nonlinear surface wave, and a novel pathway for preventing the rail failure caused by fatigue, to ensurethe safety of rail in service and the safe railway operation.Keywords: rail detection; nonlinea