Error correction method of welding residual stress ultrasonic measurement

Abstract

The invention discloses an error correction method of welding residual stress ultrasonic measurement. The method comprises A, preparing a welded test plate 1 and a welded test plate 2 from a mother material plate of a welded test piece to be detected, B, taking an arcing region sample, a stable region sample and an arc suppression region sample from the welded test plate 1, subdividing the samples according to microstructural difference, and labeling welding feature points, C, labeling welding feature points at corresponding positions of the welded test plate 2, and acquiring a thermal cycle curve by the labeling welding feature points of the welded test plate 2, D, preparing a thermal simulation block E by the thermal cycle curve, E, according to mother material small block and thermal simulation block residual stress measured by an ultrasonic method and a sectioning method, determining a residual stress corrected value, F, according to the residual stress corrected value, correcting an ultrasonic measurement residual stress measured value so that an accurate residual stress value of the welded piece to be detected is obtained. The error correction method can correct errors caused by difference of microstructures of a mother material zone and a zone to be detected and substantially improve residual stress ultrasonic measurement precision.

Description

technical field [0001] The invention relates to an error correction method for correcting the error of ultrasonically measured welding residual stress caused by the microstructure difference between a test area and a zero-stress calibration block, and belongs to the field of non-destructive testing of welding residual stress. Background technique [0002] With the rapid development of China's high-speed train rail transit, welding is a key technology in rail transit, and the quality of welding also determines the quality of high-speed train vehicles to a certain extent. The level of welding residual stress is an important criterion for evaluating welding quality, because welding residue The damage caused by stress is the main reason for the damage of welded joints, so the rapid, efficient, non-destructive monitoring and evaluation of welding residual stress level has great industrial significance. [0003] The X-ray test for residual stress can only test the thickness of ten...

AI Technical Summary

Problems solved by technology

This process does not consider the change of ultrasonic velocity caused by the difference in microstructure composition between the weldment to be tested and the base metal, so there is a certain error between the final residual stress and the actual residual stress

This error greatly reduces the accuracy of the ultrasonic method to measure the residual stress, which greatly limits the application of the ultrasonic method in the residual stress test

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