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WO2016090589A1 - Procédé de mesure non destructive et dispositif pour contrainte résiduelle de matériau de métal ultrasonore au laser - Google Patents

Procédé de mesure non destructive et dispositif pour contrainte résiduelle de matériau de métal ultrasonore au laser Download PDF

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Publication number
WO2016090589A1
WO2016090589A1 PCT/CN2014/093543 CN2014093543W WO2016090589A1 WO 2016090589 A1 WO2016090589 A1 WO 2016090589A1 CN 2014093543 W CN2014093543 W CN 2014093543W WO 2016090589 A1 WO2016090589 A1 WO 2016090589A1
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Prior art keywords
laser
residual stress
ultrasonic
signal
dual
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Ceased
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PCT/CN2014/093543
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English (en)
Chinese (zh)
Inventor
杨先明
王昱
龙绒蓉
张海霞
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YANTAI FURUN INDUSTRIAL Co Ltd
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YANTAI FURUN INDUSTRIAL Co Ltd
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Priority to PCT/CN2014/093543 priority Critical patent/WO2016090589A1/fr
Publication of WO2016090589A1 publication Critical patent/WO2016090589A1/fr
Anticipated expiration legal-status Critical
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N29/00—Investigating or analysing materials by the use of ultrasonic, sonic or infrasonic waves; Visualisation of the interior of objects by transmitting ultrasonic or sonic waves through the object

Definitions

  • the invention relates to the technical field of laser ultrasonic non-destructive testing system for residual stress of metal materials in a harsh environment, in particular to a non-destructive testing device for residual stress of metal materials in a harsh environment such as high temperature, high pressure and radiation.
  • Ultrasonic detection of the residual stress of a metal material is based on the acoustic-elastic effect of the ultrasonic wave, that is, when the ultrasonic wave propagates inside the material, the stress is measured by the acoustic birefringence effect caused by the stress.
  • the traditional method of laser ultrasonic non-destructive testing of residual stress in metal materials is to use Nd:YAG pulsed laser to excite surface waves and receive them with a self-difference laser interferometer.
  • the residual stress distribution of the material is reflected by measuring the relative change of surface acoustic velocity at different positions.
  • the self-difference laser interferometer detection principle is that the ultrasonic vibration of the sample surface is u(t), and the phase shift of the laser pulse reflected by the sample surface is 4 ⁇ u(t)/ ⁇ , the light intensity after the two beams are dried.
  • the expression is:
  • S is the effective intensity transmission coefficient of the reference beam
  • Q is the transmission coefficient of the effective intensity of the reflected beam of the sample surface
  • ⁇ (t) is the phase
  • t is the time.
  • the phase ⁇ (t) is determined by the optical path difference of the interferometer and is affected by external vibration. Therefore, when there is environmental vibration or vibration of the sample to be inspected, the accuracy of the residual force of the measurement is seriously affected.
  • the residual stress measurement method using the piezoelectric probe for receiving, the piezoelectric probe must be coupled with the workpiece to be tested by the coupling agent, so it is not applicable to the residual stress test environment of high temperature, corrosion and radiation; other non-contact laser Ultrasonic optical measurement methods such as blade detection technology measurement principle is that when the diameter of the probe beam irradiated onto the surface of the sample is less than the length of the ultrasonic wave, the reflected detection beam is deflected by the surface ultrasonic wave, and the deflection is received by the displacement sensitive detector. The amplitude and nature of the ultrasonic wave are related. This method can show the propagation of surface waves and body waves, and detect the internal defects and microstructure of the sample. The method has the advantages of simple structure, frequency bandwidth and small influence of environmental vibration, and is an effective tool for ultrasonic detection of polished surface samples, but can only be measured by residual stress of metal materials with high smooth surface.
  • Laser ultrasonic non-destructive testing equipment for residual stress of traditional metal materials ultrasonic residual stress detection method and equipment using self-difference laser interferometer, limited by the principle of self-differential measurement technology, when external environment vibration Or when the sample to be tested is vibrated, the measurement residual stress is very low precision, so it can only be used in the vibration-free environment or the residual stress measurement under the condition that the sample to be tested is very stable; other laser ultrasonic optical detection methods such as the blade detection technology require the sample to be inspected.
  • the surface is very smooth and requires high reflective laser performance. However, in the measurement of residual stress of actual metal materials, many metal surfaces are matt, and the shape is irregular and the surface roughness is high. Therefore, the method is applied.
  • the piezoelectric probe must be coupled with the workpiece to be tested by the coupling agent, so it is not suitable for the residual stress test environment of high temperature, corrosion and radiation; the piezoelectric probe is limited by its technical principle and cannot At the same time, longitudinal wave, transverse wave and surface wave are generated, so it can only be applied to the measurement of two-dimensional residual stress; when detecting residual stress, the piezoelectric probe requires full contact with the workpiece to be inspected. If the contact is not good, the measurement value error will occur. Therefore, it is not applicable to the measurement of the residual stress of the workpiece with a complicated shape, the application Domain also very restricted.
  • the invention relates to a non-destructive measuring method and device for residual stress of laser ultrasonic metal material, wherein the device comprises a pulse laser, a detecting laser, a fiber detector, a double-wave mixing optical interferometer, a data acquisition and control card, and a computer;
  • the optical fiber detector is respectively connected to the pulsed laser, the detecting laser and the dual-wave mixing optical interferometer, and the detecting laser is further connected to the dual-wave mixing optical interferometer;
  • the data acquisition and control The front end of the card is connected to the dual-wave mixing optical interferometer, and the back end of the data acquisition and control card is connected to the computer.
  • the pulsed laser and the detecting laser employ a Nd:YAG laser having a pulse width of 10 ns and a wavelength of 1064 nm.
  • the data acquisition and control card is based on a PC-DAQ data acquisition system.
  • the present invention also provides a non-destructive measurement method according to the residual stress of the laser ultrasonic metal material, the method comprising the following steps:
  • the pulsed laser is excited to generate ultrasonic waves, and the detecting laser is used to emit a detecting laser.
  • the ultrasonic wave encounters residual stress, it is reflected back to the surface of the sample to cause surface deformation, and the detecting laser encounters the deformed sample surface, and the returned laser signal occurs.
  • the change is detected by the dual-wave mixing optical interferometer, and a defect signal is generated, which is sent to a computer for processing by the data acquisition and control card, and a double-wave mixing laser ultrasonic measurement method for calculating a residual stress of the metal material is established. It is then inverted by the LabVIEW detection software to the residual stress value inside the sample, which is displayed on the computer screen in the form of curve imaging.
  • Double-wave mixing laser optical interference technology is applied to measure the residual stress of metal materials in vibration environment.
  • the positive effect of this innovation is that it is designed and manufactured by the principle of dual-wave mixing interference optical detection technology.
  • the photorefractive crystal is a lithium niobate crystal, which can receive multiple scattered spots on the surface of the sample. Therefore, the collection ability of the light wave is very strong, and the in-plane displacement and the off-plane displacement can be simultaneously measured for the rough surface, and the precision can reach the sub-pici level.
  • non-contact laser ultrasonic receiving technology using non-contact laser ultrasonic receiving technology, can achieve non-contact measurement, to meet the high temperature, corrosion, radiation metal material residual stress test environment.
  • the positive effect of this innovation point is that the non-contact laser ultrasonic receiving technology is to use the laser to irradiate the workpiece to be inspected, and the ultrasonic wave is generated based on the thermoelastic theory, and the non-contact measurement can be realized without the technique of the workpiece to be inspected, thus satisfying High temperature, corrosion, and radiation metal material residual stress test environment.
  • Figure 1 is a schematic diagram of the detection technique of the dual-wave mixing interferometer
  • FIG. 2 is a schematic view showing the system structure of a non-destructive measuring device for residual stress of a laser ultrasonic metal material according to the present invention.
  • Double-wave mixing laser ultrasonic optical interference technology the detection principle is that in the process of double-wave hybrid interference, the photorefractive crystal is equivalent to an adaptive beam splitter, and the distorted signal light and reference light energy are in the photorefractive crystal. Interference processing is performed after real-time correction is obtained.
  • the schematic diagram of the double-wave hybrid interference is shown in Figure 1.
  • the surface-reflected signal beam carrying the ultrasonic defect signal and the reference beam emitted by the laser are simultaneously incident into the photorefractive crystal.
  • the two beams of light interfere in the crystal and form a dynamic holographic grating, and the reference beam is passed through the dynamic grating. Diffraction in a dynamic holographic grating becomes a "distortion" signal that is identical to the front of the signal light, and the signal interferes with the signal beam that is "distorted" by external environmental vibrations.
  • a dynamic grating formed by interference between a signal beam and a reference beam is mainly used to correct the reference beam and the signal beam so that they can sufficiently interfere in the photoreceiver, and the vibration caused by the ultrasonic wave will It is demodulated in the form of light intensity to achieve the purpose of measuring the surface vibration of the sample, and a high-voltage electric field can be applied to the crystal to improve the coupling efficiency. It can be seen from the principle that in the actual detection, the waveform of the signal beam is inevitably caused by the surface roughness of the test piece or the vibration of the surrounding environment, so that the dual-wave hybrid interference device can pass the grating hologram established in the crystal.
  • Performing real-time corrections does not have a negative effect on the superposition of the output waveforms. Even scattered light with severe distortion of the wavefront can be detected, making it suitable for rough surfaces.
  • the photorefractive crystal has high-pass filtering function, it can cut off low-frequency noise, so it has strong resistance to external interference and can resist the surrounding environment. The effect of disturbance on the measurement.
  • optical signal diffracted from the photorefractive crystal can be expressed as:
  • a R represents the amplitude
  • ⁇ opt is the angular frequency of the reference light
  • ⁇ (t) is the phase modulated by the dynamic grating
  • ⁇ , ⁇ , and L are respectively expressed as the gain, absorption coefficient, and length of the photorefractive crystal.
  • the signal light passes through the photorefractive crystal, it is not interfered by the diffracted light, so the signal light can be expressed as:
  • the signal output through the photoelectric converter is:
  • 2k opt u(t) is the amount of phase change caused by the vibration of the ultrasonic residual stress signal. It can be concluded from formula (3) that the output signal is proportional to the displacement of the residual stress ultrasound, and the time of the movement of the ultrasonic wave in the test block can be calculated by using the light intensity signal, and then the time point of the residual stress signal is obtained, and then the calculation can be performed. The exact location of the residual stress in the test block.
  • the two-dimensional wave mixing interferometer of the device is designed and manufactured by the principle of double-wave mixing interference optical detection technology.
  • the photorefractive crystal is a lithium niobate crystal and can receive multiple surfaces of the sample. Scattering the light spot, therefore, the ability to collect light waves is very strong, and the in-plane displacement and the out-of-plane displacement can be simultaneously measured for the rough surface, and the precision can reach the sub-pici level.
  • the device uses a Nd:YAG laser with a pulse width of 10 ns and a wavelength of 1064 nm as the laser ultrasonic excitation source and detection laser source.
  • the laser ultrasonic optical receiving system adopts a two-dimensional wave mixing interferometer, and the device software uses LabView to develop the residual stress of the metal material.
  • Measurement software, system hardware based on PC-DAQ data acquisition system, the equipment workflow is pulse laser used to stimulate the generation of ultrasonic waves, detection laser is used to emit detection laser, after the ultrasonic encounters residual stress, it is reflected back to the surface of the sample, causing surface deformation The detection laser encounters the deformed sample surface, and the returned laser signal changes.
  • a defect signal is generated, which is sent to the computer through the data acquisition card for processing, and the method is used to establish a double Wave-mixed laser ultrasonic measurement of the residual stress calculation model of metal materials, and then inverted by LabVIEW detection software into the residual stress value inside the sample, displayed on the computer screen in the form of curve imaging; the structure of the equipment system is shown in Figure 2.

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  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
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  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)

Abstract

L'invention concerne un procédé de mesure non destructive et un dispositif pour la contrainte résiduelle d'un matériau de métal ultrasonore au laser. Le dispositif comprend un laser à impulsions, un laser de détection, un détecteur à fibre optique, un interféromètre optique à mélange de fréquences à deux ondes, une carte de commande et de collecte de données et un ordinateur. Le détecteur à fibre optique est raccordé séparément au laser à impulsions, au laser de détection et à l'interféromètre optique à mélange de fréquences à deux ondes. Le laser de détection est en outre raccordé à l'interféromètre optique à mélange de fréquences à deux ondes. L'extrémité avant de la carte de commande et de collecte de données est raccordée à l'interféromètre optique à mélange de fréquences à deux ondes et l'extrémité arrière de la carte de commande et de collecte de données est raccordée à l'ordinateur. Le dispositif présente une forte capacité de collecte d'onde de lumière, peut mesurer le déplacement dans le plan et hors du plan d'une surface rugueuse et peut atteindre une précision du niveau sous-picométrique. Le dispositif réalise une mesure sans contact sans zone aveugle de la contrainte résiduelle d'une pièce de travail en matériau de métal détectée dans un environnement de test à haute température, forte corrosion et fort rayonnement.
PCT/CN2014/093543 2014-12-11 2014-12-11 Procédé de mesure non destructive et dispositif pour contrainte résiduelle de matériau de métal ultrasonore au laser Ceased WO2016090589A1 (fr)

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Cited By (14)

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Publication number Priority date Publication date Assignee Title
CN108088801A (zh) * 2017-12-07 2018-05-29 电子科技大学 基于90°光混频器的激光无损检测装置
CN108168747A (zh) * 2018-02-11 2018-06-15 浙江大学 一种基于激光超声的工件表面残余应力测量装置及其方法
CN109270464A (zh) * 2018-07-31 2019-01-25 华南理工大学 基于超声波的铅酸蓄电池汇流条温度应力检测方法和装置
CN109444265A (zh) * 2018-12-19 2019-03-08 莆田学院 一种激光超声振动检测装置及方法
CN110501424A (zh) * 2019-08-19 2019-11-26 国家电网有限公司 一种激光超声的全光型耐张线夹无损检测装置
CN110824009A (zh) * 2019-11-04 2020-02-21 中国人民解放军空军工程大学 针对复合材料筒体结构的激光超声可视化检测设备及方法
CN113720508A (zh) * 2021-08-12 2021-11-30 浙江省电力锅炉压力容器检验所有限公司 基于双激光扫描的支柱瓷绝缘子应力监测装置及方法
CN113884572A (zh) * 2021-08-18 2022-01-04 侬泰轲（昆山）检测科技有限公司 一种激光超声检测方法
CN114689514A (zh) * 2021-10-10 2022-07-01 南京理工大学 一种基于激光超声理论的金属应力分布检测系统
CN114910203A (zh) * 2022-06-21 2022-08-16 武汉大学 基于激光同步诱导超声表面波与空气波的材料表面应力检测方法
CN116046234A (zh) * 2022-12-03 2023-05-02 北京翔博科技股份有限公司 基于时间调制的激光超声残余应力检测方法、系统、设备及介质
CN116202968A (zh) * 2023-03-13 2023-06-02 哈尔滨工业大学（威海） 一种增材钛合金激光超声缺陷检测系统及激光超声相位相干成像检测方法
CN117269327A (zh) * 2023-09-19 2023-12-22 浙江大学 一种激光超声亚表面缺陷检测定位方法及装置
CN117664405A (zh) * 2023-11-12 2024-03-08 中国航空工业集团公司洛阳电光设备研究所 一种硅橡胶固化应力测试方法及工装

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Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108088801A (zh) * 2017-12-07 2018-05-29 电子科技大学 基于90°光混频器的激光无损检测装置
CN108168747A (zh) * 2018-02-11 2018-06-15 浙江大学 一种基于激光超声的工件表面残余应力测量装置及其方法
CN109270464A (zh) * 2018-07-31 2019-01-25 华南理工大学 基于超声波的铅酸蓄电池汇流条温度应力检测方法和装置
CN109270464B (zh) * 2018-07-31 2024-05-17 华南理工大学 基于超声波的铅酸蓄电池汇流条温度应力检测方法和装置
CN109444265A (zh) * 2018-12-19 2019-03-08 莆田学院 一种激光超声振动检测装置及方法
CN109444265B (zh) * 2018-12-19 2024-04-02 莆田学院 一种激光超声振动检测装置及方法
CN110501424A (zh) * 2019-08-19 2019-11-26 国家电网有限公司 一种激光超声的全光型耐张线夹无损检测装置
CN110824009A (zh) * 2019-11-04 2020-02-21 中国人民解放军空军工程大学 针对复合材料筒体结构的激光超声可视化检测设备及方法
CN113720508B (zh) * 2021-08-12 2023-07-07 浙江省电力锅炉压力容器检验所有限公司 基于双激光扫描的支柱瓷绝缘子应力监测装置及方法
CN113720508A (zh) * 2021-08-12 2021-11-30 浙江省电力锅炉压力容器检验所有限公司 基于双激光扫描的支柱瓷绝缘子应力监测装置及方法
CN113884572A (zh) * 2021-08-18 2022-01-04 侬泰轲（昆山）检测科技有限公司 一种激光超声检测方法
CN114689514A (zh) * 2021-10-10 2022-07-01 南京理工大学 一种基于激光超声理论的金属应力分布检测系统
CN114910203B (zh) * 2022-06-21 2023-01-17 武汉大学 基于激光同步诱导超声表面波与空气波的材料表面应力检测方法
CN114910203A (zh) * 2022-06-21 2022-08-16 武汉大学 基于激光同步诱导超声表面波与空气波的材料表面应力检测方法
CN116046234A (zh) * 2022-12-03 2023-05-02 北京翔博科技股份有限公司 基于时间调制的激光超声残余应力检测方法、系统、设备及介质
CN116202968A (zh) * 2023-03-13 2023-06-02 哈尔滨工业大学（威海） 一种增材钛合金激光超声缺陷检测系统及激光超声相位相干成像检测方法
CN116202968B (zh) * 2023-03-13 2024-05-03 哈尔滨工业大学（威海） 一种增材钛合金激光超声缺陷检测系统及激光超声相位相干成像检测方法
CN117269327A (zh) * 2023-09-19 2023-12-22 浙江大学 一种激光超声亚表面缺陷检测定位方法及装置
CN117269327B (zh) * 2023-09-19 2024-08-13 浙江大学 一种激光超声亚表面缺陷检测定位方法及装置
CN117664405A (zh) * 2023-11-12 2024-03-08 中国航空工业集团公司洛阳电光设备研究所 一种硅橡胶固化应力测试方法及工装

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