Nonlinear ultrasound evaluating method for impact fatigue damage of metal bonding interface

Abstract

The invention discloses a nonlinear ultrasound evaluating method for impact fatigue damage of a metal bonding interface, belonging to the field of ultrasonic nondestructive detection. According to the nonlinear ultrasound evaluating method, the defect of insensitivity in material mechanical performance degradation by parameters such as sound velocity, attenuation and impedance of ultrasonic waves is overcome, and the impact damage degree is objectively evaluated through a nonlinear coefficient. A testing method comprises the steps: firstly, testing an initial nonlinear coefficient of a material bonding interface, secondly, performing an impact test on a bonding structure, determining a nonlinear coefficient once every impacting for a certain times until the bonding structure is damaged; and regularizing the nonlinear coefficient, and establishing a curve relationship of the regularized nonlinear coefficient and the relative fatigue life. As a result, the regularized nonlinear coefficient is increased with the increase of the relative fatigue life. According to the nonlinear ultrasound evaluating method, a fatigue life relation of the metal bonding structure under an impact is established, an effective nondestructive detection method is provided for a large industrial bonding facility bearing the impact in future, and a great significance is obtained for ensuring the safety operation of industrial equipment and predicting the service life of the equipment.

Description

technical field [0001] The invention belongs to the technical field of ultrasonic detection, and in particular relates to a nonlinear ultrasonic detection of impact fatigue damage on a metal bonding interface, which can perform effective quantitative evaluation. Background technique [0002] At present, as a new technology, modern bonding technology has been widely used in many industrial fields. For example, in the aircraft manufacturing industry, more than 311,000 parts and 16,000 assembly processes can be saved after the aircraft fuselage adopts bonding technology, which reduces the structural mass by 15% and saves the total cost by 25%-35%. Not only that, but the amount of adhesive is also increasing. A Boeing 747 aircraft and a C-5A Galaxy aircraft use a film area of ​​16200m 2 . Bonding technology is also widely used in manned and unmanned spacecraft, such as antennas, refrigeration plates, impact dampers and other important components are fixed on the spacecraft by ...

AI Technical Summary

Problems solved by technology

[0005] In order to overcome the shortcomings of the ultrasonic testing technology in detecting the bonding quality, the sound velocity, attenuation, impedance and other parameters of the wave are not sensitive to the degradation of the mechanical properties of the material, and cannot make accurate judgments. This invention proposes a metal bonding structure under the action of impact load Non-linear Ultrasonic Nondestructive Testing Method for Fatigue Damage

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