A method for non-destructive detection of material texture by laser ultrasonic

Abstract

The invention belongs to the field of non-destructive testing and relates to a method for non-destructive testing of material texture by laser ultrasonic. The steps of the method are as follows: measurement; imaging; correction; secondary imaging; the present invention proposes a method for non-contact and non-destructive rapid detection of material texture using laser ultrasound, which is beneficial to non-destructive detection of material micro texture. The change of the ultrasonic surface wave velocity excited by the laser measures the grain orientation distribution map to reflect the material texture. The sample is placed directly on the test bench, and the sample detection area is only limited by the movement range of the test bench. The detection area is flexible and the detectable range is large. Second, the laser spot used in the present invention can be adjusted, so that the single measurement range can be changed. Correspondingly, the measurement spatial resolution can be adjusted. In the case of low spatial resolution requirements, high detection efficiency can be obtained. Third, the surface of the sample can be polished without polishing, and has low requirements on the sample, which is especially suitable for large-scale scanning.

Description

technical field

[0001] The invention relates to a method for non-destructive detection of material texture by laser ultrasonic, belonging to the field of non-destructive detection. Background technique

[0002] The structure in which the polycrystalline orientation distribution state obviously deviates from the random distribution is called texture. Many materials require their texture to be detected in order to analyze and predict their performance. The grain orientation distribution diagram is the most intuitive way to characterize the material texture. Method, the method that can obtain grain orientation distribution map at present is mainly electron backscatter diffraction (EBSD) method, but, there are following three problems in this method: first, electron backscatter diffraction (EBSD) method is based on an annex of scanning electron microscope, The sample to be tested must be able to meet the requirements of scanning electron microscopy. The length, width and height ...

Examples

Embodiment 1

[0055] For titanium alloy forgings with grade TA11, the testing steps are as follows:

[0056] (1) measurement

[0057] 1.1 Sample requirements and placement

[0058] The plane to be tested of the sample to be tested is polished, and the sample to be tested is placed on the two-dimensional mobile worktable to ensure that the plane to be tested is parallel to the surface of the two-dimensional mobile workbench.

[0059] 1.2 Adjust the optical path

[0060] According to the order of the pulse laser with a wavelength of 1064nm, the aperture with a diameter of 2mm, the grating with a pitch of 0.1mm, the lens with a diameter of 5mm, and the dichroic mirror that can transmit light with a wavelength of 1064nm and reflect light with a wavelength of 532nm at 90° The excitation equipment is composed of a continuous laser with a wavelength of 532nm, an aperture with a diameter of 2mm, a polarization beam splitter, a quarter glass slide and a laser interferometer in order to form a rece...

Embodiment 2

[0077] For titanium alloy forgings with grade TC4, the detection steps are as follows:

[0078] (1) measurement

[0079] 1.1 Sample requirements and placement

[0080] The plane to be tested of the sample to be tested is polished, and the sample to be tested is placed on the two-dimensional mobile worktable to ensure that the plane to be tested is parallel to the surface of the two-dimensional mobile workbench.

[0081] 1.2 Adjust the optical path

[0082] According to the order of the pulse laser with a wavelength of 1064nm, the aperture with a diameter of 532nm, the grating with a pitch of 0.05mm, the lens with a diameter of 4mm, and the dichroic mirror that can transmit light with a wavelength of 1064nm and reflect light with a wavelength of 532nm at 90° The excitation equipment is composed, and the receiving equipment is composed of a continuous laser with a wavelength of 532nm, an aperture with a diameter of 4mm, a polarization beam splitter, a quarter glass slide and a...

technical field

[0001] The invention relates to a method for non-destructive detection of material texture by laser ultrasonic, belonging to the field of non-destructive detection. Background technique

[0002] The structure in which the polycrystalline orientation distribution state obviously deviates from the random distribution is called texture. Many materials require their texture to be detected in order to analyze and predict their performance. The grain orientation distribution diagram is the most intuitive way to characterize the material texture. Method, the method that can obtain grain orientation distribution map at present is mainly electron backscatter diffraction (EBSD) method, but, there are following three problems in this method: first, electron backscatter diffraction (EBSD) method is based on an annex of scanning electron microscope, The sample to be tested must be able to meet the requirements of scanning electron microscopy. The length, width and height ...

Examples

Embodiment 1

[0055] For titanium alloy forgings with grade TA11, the testing steps are as follows:

[0056] (1) measurement

[0057] 1.1 Sample requirements and placement

[0058] The plane to be tested of the sample to be tested is polished, and the sample to be tested is placed on the two-dimensional mobile worktable to ensure that the plane to be tested is parallel to the surface of the two-dimensional mobile workbench.

[0059] 1.2 Adjust the optical path

[0060] According to the order of the pulse laser with a wavelength of 1064nm, the aperture with a diameter of 2mm, the grating with a pitch of 0.1mm, the lens with a diameter of 5mm, and the dichroic mirror that can transmit light with a wavelength of 1064nm and reflect light with a wavelength of 532nm at 90° The excitation equipment is composed of a continuous laser with a wavelength of 532nm, an aperture with a diameter of 2mm, a polarization beam splitter, a quarter glass slide and a laser interferometer in order to form a rece...

Embodiment 2

[0077] For titanium alloy forgings with grade TC4, the detection steps are as follows:

[0078] (1) measurement

[0079] 1.1 Sample requirements and placement

[0080] The plane to be tested of the sample to be tested is polished, and the sample to be tested is placed on the two-dimensional mobile worktable to ensure that the plane to be tested is parallel to the surface of the two-dimensional mobile workbench.

[0081] 1.2 Adjust the optical path

[0082] According to the order of the pulse laser with a wavelength of 1064nm, the aperture with a diameter of 532nm, the grating with a pitch of 0.05mm, the lens with a diameter of 4mm, and the dichroic mirror that can transmit light with a wavelength of 1064nm and reflect light with a wavelength of 532nm at 90° The excitation equipment is composed, and the receiving equipment is composed of a continuous laser with a wavelength of 532nm, an aperture with a diameter of 4mm, a polarization beam splitter, a quarter glass slide and a...