Page 51 - 《应用声学》2022年第5期
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第 41 卷 第 5 期                                                                       Vol. 41, No. 5
             2022 年 9 月                          Journal of Applied Acoustics                 September, 2022

             ⋄ 研究报告 ⋄



                     铝合金板疲劳微裂纹超声红外成像检测的

                                            数值及实验研究                        ∗





                                    韩 梦 尹嘉雯 黄军科 李 伟 魏 勤                               †


                                                (江苏科技大学理学院      镇江   212100)

                摘要：超声红外成像检测技术是一种发展迅速的新型无损检测技术，可用于检测材料表面或近表面的缺陷，由
                于对缺陷具有选择性加热的特点，近年来备受检测行业的关注。该文在铝合金板中制作疲劳微裂纹，在板中激
                励声波，裂纹表面因振动摩擦生热，用红外摄像仪记录板表面温度分布。拍摄的红外图像序列经傅里叶变换后
                得到的幅值和相位图能清晰显示裂纹的特征，测量到的裂纹长度误差达到 4.3%。用有限元模拟超声在板中裂
                纹处的生热过程，研究板中超声在裂纹处的励热机制。超声激励时间、裂纹表面间摩擦系数和裂纹开口宽度直
                接影响裂纹处的励热效果，最高温度通常位于裂纹尖端附近。模拟和实验结果均表明超声红外成像检测技术
                能对板中疲劳微裂纹实现快速检测，提供有效、可信的检测结果。
                关键词：超声红外成像；微裂纹；励热机制；温度场
                中图法分类号: TG115.28           文献标识码: A          文章编号: 1000-310X(2022)05-0727-08
                DOI: 10.11684/j.issn.1000-310X.2022.05.006


                  A comprehensive numerical and experimental study on detecting fatigue
                          microcrack in aluminum alloy plate by vibro-thermography


                                HAN Meng YIN Jiawen HUANG Junke LI Wei WEI Qin

                           (School of Science, Jiangsu University of Science and Technology, Zhenjiang 212100, China)

                 Abstract: Vibro-thermography (VT) is a new nondestructive testing technique with rapid development that
                 can be used to detect surface and sub-surface defects. Due to its selective heating characteristic to defects,
                 VT has been gaining more attention in non-destructive testing industry. In this paper, fatigue microcrack
                 was made in aluminum alloy plate and under ultrasonic excitation the heat generated by friction at the crack
                 surfaces. The surface temperature distribution was recorded by an infrared camera. The Fourier transform was
                 implemented to process thermographic sequence, and the characteristics of fatigue crack was clearly revealed
                 from the generated amplitude and phase images. The error of the crack length measured in phase image
                 is about 4.3%. The heat generation process at the crack was also simulated by finite element method, the
                 mechanism on heat generation was studied. The heat generation effect at the crack is directly affected by
                 ultrasonic excitation time, friction coefficient and opening width of crack. The highest temperature is usually
                 near the crack tip. Both the simulation and experimental results demonstrate VT can achieve rapid detection
                 of fatigue microcrack in plate, and provide effective and reliable detection results.
                 Keywords: Vibro-thermography; Microcrack; Heat generation mechanism; Temperature field


             2021-07-21 收稿; 2021-10-11 定稿
             国防基础科研计划项目 (JCKYS2020603C014), 江苏省研究生科研与实践创新计划项目 (KYCX21_3474)
             ∗
             作者简介: 韩梦 (1997– ), 女, 安徽阜阳人, 硕士研究生, 研究方向: 无损检测。
             † 通信作者 E-mail: weiqin@just.edu.cn
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