Method for detecting average crystal grain size of weld seam by utilizing weld seam characteristic guide waves

Abstract

The invention discloses a method for non-destructively detecting the average crystal grain size of a weld seam by utilizing weld seam characteristic guide waves and belongs to the field of non-destructive detection. The method comprises the steps of: sequentially distributing three sensor probes along the weld seam, wherein the three probes are away from one another by a certain distance; generating a single-audio signal by a function generator, exciting weld seam characteristic guide waves in the weld seam by a power amplifying module and an exciting sensor, respectively receiving guide wave signals excited by the first probe by using the second probe and the third probe as receiving sensors, and transmitting the guide wave signals to an oscilloscope; determining the amplitude values of the two receiving probes and calculating attenuation coefficients of the guide wave signals; and judging the average crystal grain size in the weld seam by calculating the attenuation coefficients. The method is capable of detecting the average crystal grain size of the weld seam without destructing the weld seam, and has the advantages of high efficiency, low cost and the like.

Description

Technical field [0001] The invention relates to a welding seam characteristic guided wave detection method for the average grain size of a weld seam, which uses the characteristic guided wave of the weld seam to perform non-destructive detection of the average crystal grain size in the weld of tailor-welded blanks or special equipment such as large pressure vessels And the method of characterization belongs to the field of non-destructive testing. Background technique [0002] The mechanical properties of most polycrystalline materials, such as strength and toughness, are related to the grain size. The weld area is the key connection part of many large components, and the requirements for mechanical properties are high. Therefore, the average grain size of the weld is checked. The safety of materials is very important. [0003] At present, the determination of material grain size mainly adopts the traditional metallographic method, that is, direct observation under a microscope. F...

AI Technical Summary

Problems solved by technology

[0005] At present, there are no relevant reports on the use of weld characteristic guided waves to detect the average grain size in welds at home and abroad.

Images