作者：陈选民1, 陈峰2
作者单位：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
关键词：钢轨检测;非线性表面波;服役年限;疲劳损伤
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。
Experimental investigation of rail fatigue in service using nonlinear surface wave
CHEN Xuanmin1, CHEN Feng2
1. College of Railway Transportation, Guangzhou Railway Polytechnic, Guangzhou 510430, China;
2. School of Traffic and Transportation Engineering, Central South University, Changsha 410075, China
Abstract: The paper studied the rail fatigue characteristics with different service years by using nonlinear surface waves, then derived the relative nonlinear surface wave parameter. It adopted angle beam wedge transducers to measure the propagation of nonlinear surface waves in the cross section of rails with the service years of 0, 1, 2, 5, 10, 15 and 20 respectively and analyzed the laws of nonlinear surface wave parameters. The results showed that, the change of the nonlinear parameter of rail at the initial stage of service was very small, and the nonlinear parameter of rail increased with the increase of service year. According to the metallographic analysis, it was found that the main reason for the increase of nonlinear parameter was the micro-crack caused by the increase of dislocation density. This paper will provide theoretical basis for evaluation of the rail fatigue through nonlinear surface wave, and a novel pathway for preventing the rail failure caused by fatigue, to ensure the safety of rail in service and the safe railway operation.
Keywords: rail detection;nonlinear surface wave;service year;fatigue failure
2018, 44(8): 32-36 收稿日期: 2017-12-28;收到修改稿日期: 2018-01-24
基金项目: 国家自然科学基金（51525541）；铁路总公司科技研究开发计划课题（2014G001-E）
作者简介: 陈选民(1963-),男,湖南湘潭市人,副教授,主要从事轨道超声无损检测方法研究
参考文献
[1] 何华武. 中国高速铁路创新与发展[J]. 中国铁路, 2010(12):5-8.
[2] 张书增, 李雄兵, 杨岳,等. 钢轨轨头内多元高斯声场模拟及其缺陷响应[J]. 铁道学报, 2014, 36(1):76-80.
[3] 张龙平, 杨飞. DGTC-80型地铁钢轨探伤车[J]. 机车电传动, 2017(2):90-92.
[4] 邓建辉. 钢轨裂缝缺陷分析[J]. 理化检验-物理分册, 2002, 38(8):360-362.
[5] 张书增, 杨岳, 刘希玲, 等. 基于探头声场特性的钢轨超声检测研究[J]. 铁道科学与工程学报, 2013, 10(5):123-128.
[6] 税国双, 汪越胜, QU J M, 等. 利用直接激发Rayleigh表面波的方法测量材料的声学非线性系数[J]. 声学学报, 2008, 33(4):378-384.
[7] 颜丙生, 刘自然, 张跃春, 等. 非线性超声检测镁合金早期疲劳的试验研究[J]. 机械工程学报, 2013, 49(2):20-24.
[8] HAMILTON M F, BLACKSTOCK D T. Nonlinear Acoustic[M]. America:Academic Press, 1998:25-39.
[9] 颜丙生, 吴斌, 李佳锐, 等. 金属材料力学性能退化非线性超声检测实验系统优化[J]. 仪表技术与传感器, 2011(2):95-98.
[10] KIM J Y, JACOBS L J, QU J, et al. Experimental characterization of fatigue damage in a nickel-base superalloy using nonlinear ultrasonic waves[J]. J. Acoust. Soc. Am., 2006, 120(3):1266-1273.
[11] XIANG Y, DENG M, XUAN F, et al. Cumulative second-harmonic analysis of ultrasonic Lamb waves for ageing behavior study of modified-HP austenite steel[J]. Ultrasonics, 2011(51):974-981.
[12] TORELLO D, THIELE S,MATLACK K H, et al. Diffraction, attenuation, and source corrections for nonlinear Rayleigh wave ultrasonic measurements[J]. Ultrasonics, 2015(56):417-426.
[13] HERRMAN J, KIM J Y, JACOBS L J, et al. Assessment of material damage in a nickel-based superalloy using nonlinear Rayleigh surface waves[J]. J. Appl. Phys., 2006, 99(12):124913.
[14] SHULL D J, KIM E E, HAMILTON M F, et al. Diffraction effects in nonlinear Rayleighwave beams[J]. J. Acoust. Soc. Am., 1995, 97(4):2126-2137.
[15] XIANG Y, DENG M, XUAN F. Thermal degradation evaluation of HP40Nb alloy steel after long term service using a nonlinear ultrasonic technique[J]. Journal of Nondestructive Evaluation, 2014, 33(2):279-287.
[16] LEE T H, JHANG K Y. Experimental investigation of nonlinear acoustic effect at crack[J]. NDT&E Int, 2009, 42(8):757-764.
