Assessment of the Length and Depth of Delamination-Type Defects Using Ultrasonic Guided Waves

Applied Sciences

Regina Rekuvienė¹  Vykintas Samaitis¹  Liudas Mažeika¹ 

[1] Prof. K.Baršauskas Ultrasound Research Insititute, Kaunas University of Technology, K. Baršausko St. 59, LT-51423 Kaunas, Lithuania;

关键词: structural health monitoring;    composites;    ultrasonic testing;    guided waves;    delamination;   

DOI  :  10.3390/app10155236

来源: DOAJ

【 摘 要 】

Fiber-reinforced composite laminates are being increasingly used in various engineering components in the sectors of aerospace and green energy. Due to impacts throughout the service life of the structure, matrix breakage and delaminations significantly altering the structural integrity of the laminate can occur. Hence, robust guided wave structural health monitoring systems are required to ensure continuous safety of engineering structures. In this paper, the ultrasonic method based on the analysis of A₀ mode reflecting within the defected area has been proposed to extract the length and the depth of the delamination-type defect. The technique proposed in this study extracts the depth of the damage by analyzing the magnitude variations of direct A₀ mode which are caused by the difference of wave velocities in the upper and lower sub-laminates. This results in an altering and frequency-dependent forward-scattered amplitude of direct A₀ mode. Furthermore, the proposed approach uses previously obtained information about the depth of the defect, which allows for the determination of the phase velocities of A₀ and S₀ modes in the upper and lower sub-laminates. As a result, the accuracy of the damage length estimation is increased. The performance of the proposed method was proven with 2D and 3D numerical simulations and experiments on samples with artificial defects. The method validation results showed that the proposed method with some limitations is capable of extracting the length of delamination with an approximate error below 6%.

【 授权许可】

Unknown