航空发动机涡轮叶片缺陷弱磁检测方法研究  

Weak Magnetic Methods on Detecting Defects in Aviation Engine Turbine Blade

作　　者：熊乐超 姜禹桐 孙鹏宇 张统伟 于润桥[1] XIONG Le-chao;JIANG Yu-tong;SUN Peng-yu;ZHANG Tong-wei;YU Run-qiao(Key Laboratory of Nondestructive Testing Technology(Ministry of Education),Nanchang Hangkong University,Nanchang 330063,China)

机构地区：[1]无损检测技术教育部重点实验室(南昌航空大学),南昌330063

出　　处：《失效分析与预防》2021年第3期161-165,共5页Failure Analysis and Prevention

基　　金：国家自然科学基金(51765048,51967014)。

摘　　要：针对航空发动机涡轮叶片边缘裂纹缺陷难以进行检测的难题,提出了一种基于弱磁检测技术缺陷判定方法的新算法。首先从理论上分析了弱磁检测技术对涡轮叶片边缘裂纹缺陷检测的可行性,其次,为减少检测提离高度设计了扫查工装并在地磁场环境下对人工刻伤的涡轮叶片进行弱磁检测,最后通过磁梯度法与极值法相结合的方法对原始信号进行数据处理,提取异常信号。结果表明:裂纹处磁感应强度信号变化明显,缺陷检测位置误差在2.5 mm以内;磁梯度法与极值法相结合能减少噪声干扰,提高信噪比,放大缺陷信号;裂纹深度在0.2~0.4 mm时,磁感应强度信号随裂纹深度增加而增加。该方法对深度在0.4 mm以内的涡轮叶片裂纹缺陷检测具有可行性,缺陷信号判别明显。A new algorithm for defect detection based on weak magnetic detection technology is presented to detect crack defects at the edge of turbine blade of aeroengine effectively.The feasibility of the detection technology on determining the edge crack defects in the turbine blades was theoretically evaluated.And in order to minimize the lift-off height,we designed the scanning tooling and conducted the weak magnetic detection on the artificially engraved turbine blades in the geomagnetic environment.With combining the magnetic gradient method and the extreme value methods,data processing is performed on the original signal to extract abnormal signals.The results show that the magnetic induction intensity signal at the crack has obvious changes,and the defect detection position error is less than 2.5 mm.The combination of magnetic gradient method and extreme value method can reduce noise interference,increase the signal-to-noise ratio,and amplify the defect signal.When the crack depth ranges from 0.2 to 0.4 mm,the intensity magnetic induction signal increases with the crack depth.Therefore,the proposed method is available for the flaw detection in turbine blades with a depth of less than 0.4 mm,and corresponding signal identification is obvious.

关 键 词：弱磁检测 涡轮叶片 裂纹检测 边缘检测 缺陷提取 

分 类 号：TG115.28[金属学及工艺—物理冶金]