Method for welding line ultrasound array full focusing imaging based on oblique incidence longitudinal waves

Abstract

The invention discloses a method for welding line ultrasound array full focusing imaging based on oblique incidence longitudinal waves. A present array imaging postprocessing method is only applied to processing of full matrix data collected under the situation that a phased array probe acoustic beam vertically enters a to-be-tested piece. According to the method, a wedge block is added to a phased array probe, a main acoustic beam of longitudinal waves enters a welding line of the to-be-tested piece through the wedge block; by processing the full matrix data excited and received by a phased array sensor and calculating a refraction intersection point of the acoustic beam on an interface through the wedge block based on a Snell principle, the acoustic beam propagation time of each array element reaching all imaging points is calculated, amplitudes of focus points are obtained through calculation, and then the amplitude of each focus point is focused; and finally full focusing imaging of the oblique incidence longitudinal waves is achieved. The longitudinal wave main acoustic beam in a specific direction can be generated, the defect detection effect in a welding line area and the defect recognition rate are improved; and a probe protecting effect is achieved.

Description

technical field [0001] The invention belongs to the field of non-destructive testing, and is an ultrasonic array full-focus imaging method suitable for weld seam defect detection, in particular an ultrasonic array full-focus imaging method based on oblique incident longitudinal waves. Background technique [0002] With the rapid development of modern industrial level, welding technology has been widely used in pressure vessels, ships, aerospace, power systems and other industrial fields. At present, there are many welding techniques, mainly including fusion welding, brazing, pressure welding and other welding methods. During the welding process, the weld is affected by factors such as welding equipment, welding process, material residual stress and material size, which may produce a variety of different welding defects. In addition, in the long-term service process, it may be affected by high temperature, high pressure or corrosion and other environments, and defects will a...

AI Technical Summary

Problems solved by technology

The introduction of wedges will change the propagation path and direction of the sound beam in the test block, thereby affecting the total focus imaging algorithm. At present, there is no calculation method for weld seam ultrasonic array total focus imaging based on oblique incident longitudinal waves.

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