Method and system for determining residual stress and residual elimination effect of material

Abstract

The invention provides a method and a system for determining residual stress and residual elimination effect of a material. The method comprises the following steps of setting a plurality of measuredpoints on a surface of a measured part according to a preset interval; exciting ultrasonic waves in the circumferential direction of each measured point through an ultrasonic generator, and obtainingthe distribution of the sound time difference of critical refraction longitudinal waves formed on the surface of the measured part in the circumferential direction of the measured points; and determining the main direction of the residual stress on the surface of the material according to the distribution of the critical refraction longitudinal wave sound time difference, thereby determining the residual stress of the measured part. The method is advantaged in that on one hand, the material itself cannot be damaged, on the other hand, due to the fact that the residual stress main direction ofeach measured point can be represented, the residual stress of the material can be measured more accurately, and the residual stress elimination effect of the material can be determined accurately compared with a mode that the single-direction residual stress of one or a few points is measured at present.

Description

technical field [0001] The present invention relates to the technical field of stress detection, and more specifically, to a method and system for determining residual stress of a material and an effect of eliminating residue. Background technique [0002] For materials widely used in engineering, the material components will be affected and affected by various factors such as processes during the manufacturing process; when these factors disappear, if the above-mentioned effects and influences on the material components cannot disappear completely , there is still part of the effect and influence remaining in the component, then this residual effect and influence is called residual stress or residual stress. Excessive residual stress will lead to a serious decline in the local performance of components. For important load-bearing components, failure will cause major economic losses or accidents. At present, the residual stress is still measured in the same way as the princ...

AI Technical Summary

Problems solved by technology

Excessive residual stress will lead to a serious decline in the local performance of components. For important load-bearing components, failure will cause major economic losses or accidents

At present, the residual stress is still measured in the same way as the principal stress of the material, such as using the drilling strain gauge method or X-ray diffraction method for measurement. When the strain gauge method is tested, it is necessary to use an adhesive to attach the strain gauge to the tested material. On the surface of the material, it is very inconvenient and a destructive method to drill a small hole in the attachment of the strain gauge

X-ray diffraction method is based on elastic mechanics and lattice diffraction theory, which can measure stress more accurately, but X-ray radiation is harmful to the body, and the equipment is bulky, which makes the measurement very inconvenient

At present, for welded parts, the vibration aging method or heat treatment is often used to eliminate the residual stress. Due to the uncertainty of the concentration position of the residual stress, the determination of the effect of the residual stress requires efficient large-scale detection of the tested part. The existing materials There are many limitations in the determination method of residual stress, therefore, a new technology for determining the residual stress of materials is urgently needed

Images