Laser scattering detection method for evaluating surface morphology structure of workpiece

Abstract

The invention discloses a laser scattering detection method for evaluating the surface morphology structure of a workpiece, which adopts linear polarization laser scattering to detect the polarization state distribution of back scattering light on a machined surface, and obtains the polarization state distribution of the back scattering light on the machined surface under different incident angles by changing the included angle between the incident laser and the material surface. The height fluctuation variance s2 and the related length Sal of the evaluation parameters of the texture structure and the morphology characteristics of the machined surface of the material under different incidence angles are solved, and the accurate value of the height fluctuation variance s2 and the related length Sal of the machined surface of a part is obtained through a linear regression method, so that the texture structure and the morphology characteristics of the machined surface are accurately detected and evaluated. The method is not limited by the roughness of the machined surface and the working distance, by adjusting the angle between the laser beam and the machined surface of the part and according to the accurate height fluctuation variance and the related length value of the surface of the machined material, the texture structure and the morphology characteristics of the machined surface can be evaluated more scientifically, and the method has high detection efficiency and precision.

Description

Technical field [0001] The present invention relates to a non-destructive detection technique for material processing surface morphology structure, particularly a laser scattering detection method for material processing surface morphology. Background technique [0002] The surface topographic structure of material processing is an important parameter of evaluating the surface quality of the material. The texture structure of the part machining surface is usually directly related to the performance of the parts. In most cases, the assessment of the surface quality of the part is used to use roughness arithmetic average height RA, however RA does not exactly reveal the texture structure, morphological distribution of material processing surfaces, morphological distribution. The two machining surfaces are the same, but the surface texture structure and morphological distribution of the two may be completely different, causing a variable from the performance of the part. The perform...

AI Technical Summary

Problems solved by technology

Among them, the contact probe scanning needs to contact the processing surface of the part, and its measurement accuracy is affected by the scanning speed. The actual measurement scanning speed is low and the detection efficiency is low. Macroscopic part processing surface detection; optical interferometer measurement uses Michelson interference principle to measure the height change of part processing surface, but the part processing surface should not be too rough, otherwise it will be difficult to form interference, and the actual measurement is difficult; laser confocal microscopic observation, using laser confocal Focusing microscopic principle, measuring the processed surface, the measurement efficiency is low, suitable for small-scale precision detection, not suitable for the detection of the actual macroscopic large-scale parts processing surface, and the detection effect of transparent materials will be reduced; in addition, optical interferometer measurement and Laser confocal microscopy has limitations on the working distance and needs to be inspected close to the processed surface. For actual parts, especially the detection of large-sized parts, it must be considered; laser scanning inspection uses structured light or point laser to measure the processed surface , the detection speed is fast and the efficiency is high, but for the precision machined surface, the detection result is noisy, the signal-to-noise ratio is low, and the data processing is difficult

In actual production and processing, Ra is mostly used for the evaluation of the texture structure and morphology of the processed surface, which is not scientific enough.

The precise detection and evaluation of surface texture structure and topographical features suitable for actual production and processing is still lacking.

Images