Delamination monitoring using low frequency stress wave for laminated composites

Pingyu Zhu, Zhichao Yang, Wei Shi , Yongjing Li
Abstract:
Owing to the anisotropy of composite laminates, local responses happens at periphery of the drilled hole even under the same loads. The strain measurement is probably the most sensitive and better option to detect and quantify delamination inside composite materials. In the paper, dynamic strain of the composite laminates was online monitored using fiber Bragg grating (FBG) and strain gauges. Two experiments with different sensors configurations on the specimen made of glass fiber reinforced polymers (GFRP) were conducted: mounted on the entrance and the exit side of the drilled hole. The low frequency stress wave signals contained more drilling details have been extracted from those sensors at different locations. The wavelet transforms shows the timefrequency spectrum corresponds to the delamination behaviour, especially when the drill tip contacted the first ply and pierced the last plies of the GFRP laminates.
Keywords:
drilling delamination, composite laminates, strain, Fiber Bragg grating (FBG)
Download:
IMEKO-TC10-2016-035.pdf
DOI:
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Event details
IMEKO TC:
TC10
Event name:
TC10 Workshop on Technical Diagnostics 2016
Title:

14th IMEKO TC10 Workshop “New Perspectives in Measurements, Tools and Techniques for system’s reliability, maintainability and safety”

Place:
Milano, ITALY
Time:
27 June 2016 - 28 June 2016