Laser ultrasonic non-destructive detection method for material textures

Abstract

The invention belongs to the field of non-destructive detection, and relates to a laser ultrasonic non-destructive detection method for material textures. The method comprises the following steps of measuring; imaging; correcting; secondary imaging. The laser ultrasonic non-destructive detection method for the material textures has the advantages that the material micro-texture can be favorably performed with the non-destructive detection; a grain orientation distribution map is measured according to the change of laser-excited ultrasonic surface wave speed, so as to reflect the material texture; a sample is directly put on a test bench, a sample detection area is only limited by the movement range of the test bench, the detection area is flexible, and the detection range is large; 2, the used laser spot can be adjusted, so the single measuring range can be changed, the resolution of the measuring space can be correspondingly adjusted, and the higher detection efficiency can be obtained under the condition of lower requirement on space resolution; 3, the surface of a sample only needs grinding, and does not need polishing, the requirement on the sample is low, and the method is especially suitable for the large-range 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 ...

AI Technical Summary

Problems solved by technology

[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 of the sample are difficult to exceed 50mm. For large-sized samples, it can only be detected by dividing it into small pieces. Secondly, this method uses a diameter of only a few Scanning with an electron beam of 10 microns, each measurement covers a small area. If a larger area needs to be scanned, it will take a long time for detection. Finally, this method generally requires the sample to be electrolytically polished, which takes a long time and is inefficient. In summary, existing methods are not suitable for scanning large-scale grain orientations of larger-grained materials