Ultrasonic-acoustic emission detection method for composite material

Abstract

The invention relates to an ultrasonic-acoustic emission detection method for a composite material. The method can detect internal defects of the composite material according to an acoustic emission signal excited by pulse ultrasonic waves in the composite material; an emission transducer and a receiving transducer adopt an asymmetric mode and two layouts such as a separation type and an integration type and are arranged on the same side or any side of a part of the composite material; the positions and the attitudes of the emission transducer and the receiving transducer are selected within 0-360 degrees, so that multi-channel ultrasonic-acoustic emission detection can be realized; defects can be judged and positioned according to a time domain feature of an acoustic emission signal in the detected composite material. According to the method, the composite material detection capability of ultrasonic-acoustic emission is greatly improved; the detection thickness is 50mm, and the detection sensitivity to the defects which have the diameters being phi3mm and are 0.13mm and 49mm deep is achieved; the ultrasonic-acoustic emission detection resolution, a surface detection blind area and the detection capacity are obviously improved.

Description

technical field [0001] The invention belongs to non-destructive testing technology, and relates to an ultrasonic-acoustic emission method for composite materials in the fields of aviation, aerospace, weapons, ships, metallurgy, steel, transportation, construction and the like. Background technique [0002] Ultrasound is an important method widely used in quantitative non-destructive testing of various materials and their structural defects. It has been widely used in aerospace, weapons, electronics, ships, metallurgy, petrochemical oil, transportation, construction and other fields, especially in composite materials At present, 80% of composite material structures are tested by ultrasonic testing. At present, the ultrasonic testing methods for composite materials mainly include reflection method and penetration method. Using external ultrasonic pulse sound source, the reflection / transmission sound wave behavior formed in the tested composite material is used to detect and di...

AI Technical Summary

Problems solved by technology

At present, the ultrasonic testing methods for composite materials mainly include reflection method and penetration method. Using external ultrasonic pulse sound source, the reflection / transmission sound wave behavior formed in the tested composite material is used to detect and discriminate defects. The main shortcomings are: (1) It is very sensitive to the orientation of defects. As the angle between the orientation of defects and the propagation direction of the incident sound wave increases, the ability to detect defects will decrease significantly, which will easily cause missed detection; (2) The sound wave attenuation is severe, which is difficult to achieve Non-destructive testing of materials with severe acoustic attenuation such as large-thickness composite materials and porous composite materials

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