METHOD FOR MEASURING DEVIATION ANGLE OF FATIGUE MICROCRACK BASED ON NONLINEAR ULTRASOUND

    公开(公告)号:US20230048646A1

    公开(公告)日:2023-02-16

    申请号:US17980411

    申请日:2022-11-03

    IPC分类号: G01B17/00 G01N29/04

    摘要: Disclosed is a method for measuring a deviation angle of a fatigue microcrack based on nonlinear ultrasound, comprising: preliminarily positioning a fatigue microcrack to obtain a center of the microcrack; selecting a horizontal positive direction, and defining an orientation angle; drawing a positive circumference on a surface of a metal plate, and selecting a fixed interval angle; placing an excitation sensor and a receiving sensor on the drawn positive circumference according to the orientation angle; ultrasonically testing each group of ultrasonic sensing paths, and recording time domain waveform signals formed by each group of ultrasonic sensing paths; converting each group of time domain waveform signals into a corresponding frequency domain graph, extracting an ultrasonic fundamental wave signal amplitude and a second harmonic waveform amplitude, and calculating a relative nonlinear coefficient; drawing an orientation angle-relative nonlinear coefficient polar coordinate graph; and determining a deviation angle of the microcrack.

    Method for measuring deviation angle of fatigue microcrack based on nonlinear ultrasound

    公开(公告)号:US11946735B2

    公开(公告)日:2024-04-02

    申请号:US17980411

    申请日:2022-11-03

    IPC分类号: G01B17/00 G01N29/04 G01N29/44

    摘要: Disclosed is a method fir measuring a deviation angle of a fatigue microcrack based on nonlinear ultrasound, comprising: preliminarily positioning a fatigue microcrack to obtain a center of the microcrack; selecting a horizontal positive direction, and defining an orientation angle; drawing a positive circumference on a surface of a metal plate, and selecting a fixed interval angle; placing an excitation sensor and a receiving sensor on the drawn positive circumference according to the orientation angle; ultrasonically testing each group of ultrasonic sensing paths, and recording time domain waveform signals formed by each group of ultrasonic sensing paths; converting each group of time domain waveform signals into a corresponding frequency domain graph, extracting an ultrasonic fundamental wave signal amplitude and a second harmonic waveform amplitude, and calculating a relative nonlinear coefficient; drawing an orientation angle-relative nonlinear coefficient polar coordinate graph; and determining a deviation angle of the microcrack.