基于时频分析的单频激励电磁超声测厚方法

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中图分类号：TB9;TB552;TH878 文献标志码：A文章编号：1674-5124（2025）11-0032-08

Abstract： The electromagnetic acoustic thickness measurement method serves as an effective approach for metalic thin-walled components.As wall thickness progressively decreases， conventional electromagnetic acoustic techniques exhibit signal aliasing when measuring thin-wall specimens （ .>1mm） ，failing to meet highprecision measurement requirements. Current swept-frequencyelectromagneticacoustic thickness measurement methods，while employed forultra-thin components，suffer from prolonged measurement durations and low efciency，thereby limiting practical implementation in manufacturing processes.To address these limitations，this paper presents a single-frequency excitation electromagnetic acoustic thickness measurement methodology incorporating time-frequency analysis， while developing an automatic identification algorithm for harmonic frequency peak localization. We propose a thickness calculation approach based on harmonic peak frequency differences in echo spectra， effectively resolving the aliasing issue encountered in single-frequency excitation measurements of thin-walled components.A finite element simulation model has been established to validatetheproposed method，with experimental verificationconductedon simulation results.The methodology ultimately achieved thickness measurement of 0.182mm aluminum alloy specimens with 0.002mm accuracy，demonstrating significant efficiency improvements through algorithm computation time reduced to 0.03 s per measurement.

Keywords：electromagnetic ultrasonic thickness measurement;thin-wall part;time-frequency analysis; automaticpeakrecognition

0 引言

大型薄壁零件广泛应用于航空航天领域，其壁厚直接影响航空航天结构件的有效重量和强度[]，快速精确测量薄壁零件（ >1mm. 的壁厚，是此类零件制造中不可缺少的关键环节。（剩余10137字）