Full-optical laser ultrasonic measuring method for internal defect of material

An internal defect, laser ultrasonic technology, used in the analysis of solids using sonic/ultrasonic/infrasonic waves, can solve problems such as difficulty in detecting tiny internal defects, inability to accurately locate three-dimensional positions, and great influence on surface quality, to improve excitation Efficiency, ease of operation, directional effects

An internal defect, laser ultrasonic technology, used in the analysis of solids using sonic/ultrasonic/infrasonic waves, can solve problems such as difficulty in detecting tiny internal defects, inability to accurately locate three-dimensional positions, and great influence on surface quality, to improve excitation Efficiency, ease of operation, directional effects

CN103808802AInactive Publication Date: 2014-05-21NANJING UNIV OF SCI & TECH
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  • Full-optical laser ultrasonic measuring method for internal defect of material
  • Full-optical laser ultrasonic measuring method for internal defect of material
  • Full-optical laser ultrasonic measuring method for internal defect of material

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Embodiment Construction

[0029] The invention is an all-optical laser ultrasonic measurement method for internal defects of materials, which comprises two steps,

[0030] Step 1: Measure the two-dimensional position and size of the internal defect of the tested object 6 on the x-y plane;

[0031] Step 2: Determining the depth of the internal defect of the tested object 6 in the z direction.

[0032] Step 1 is as specific as figure 1 As shown, the pulsed laser circular light source 1 is used to irradiate the surface of the measured object 6 to excite the ultrasonic bulk wave, and the ultrasonic bulk wave propagates to the inside of the measured object 6, and the laser vibrometer 14 is used to excite the probe light 2 on the measured object 6. The ultrasonic body wave is detected at the center of the other side, and the detection waveform of the ultrasonic body wave detected by the laser vibrometer 14 is recorded by the oscilloscope 13 connected to the laser vibrometer 14, and the measured object 6 is ...

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Abstract

The invention discloses a full-optical laser ultrasonic measuring method for internal defects of a material. The method comprises the following steps: firstly, measuring the two-dimensional position and the size of the internal defect of a measured object on an x-y plane, and subsequently measuring the depth of the internal defect of the measured object in the z direction. By adopting the method, the three-dimensional position and the size information of the internal defect can be obtained by scanning, and the method is high in precision and efficiency, and is applicable to non-destructive detection on various materials.

Description

technical field [0001] The invention belongs to the technical field of laser ultrasonic non-destructive testing, in particular to an all-optical laser ultrasonic measurement method for internal defects of materials. Background technique [0002] Internal defect is a kind of defect that exists widely in various workpiece materials. If it is not detected and confirmed in time, it may lead to the fracture and damage of the workpiece, which will seriously affect the production safety. However, due to the concealment of internal defects and their extensive existence in various materials, as well as the requirements of high-precision, high-speed online inspection, harsh environment and safety inspection, it is still very difficult to carry out non-destructive inspection of internal defects. The existing conventional non-destructive testing methods mainly fall into four categories: eddy current testing, magnetic particle testing, radiographic testing and ultrasonic testing. The us...

Claims

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Application Information

Patent Timeline
21 May 2014
Publication
CN103808802A
IPC
G01N29/06
Inventors
沈中华; 孙凯华