Title: In-Process Ultrasonic Cure Monitoring System for Defect Detection and Localization in Composites

Authors: Tyler B. Hudson, Kenneth M. Serrano, Abiel Amador Jr., Trenton Bryce Abbott, Frank L. Palmieri

DOI: 10.33599/nasampe/s.21.0599

Abstract: Composite materials are gaining increased use by aerospace manufacturers due to their superior strength-to-weight ratio. However, the composite manufacturing process can introduce defects such as voids and fiber waviness, which can decrease the strength and reliability of the structure. Previous technologies have been developed to non-destructively locate and quantify defects in composite parts after fabrication, but not during cure. The technology developed in this study is an ultrasonic system capable of performing non-destructive inspection of composite parts during cure in an industrial oven. An ultrasonic scanner was enclosed in a nitrogen-cooled insulating box that prevented thermal damage to the temperature-sensitive electronics. Inspection of the composite part was performed through the bottom of the enclosure, which served as the tool plate for the part. This paper will discuss the results obtained throughout the cure cycle from amplitude C-scans and B-scans of a composite panel with intentionally embedded defects. Hollow glass microspheres of various amounts were embedded between plies of a carbon fiber reinforced polymer (CFRP) laminate to simulate porosity. The simulated porosity in the composite laminate was detected and localized throughout the cure cycle. This initial testing will aid in the transition of this system from an industrial oven to an autoclave, which is the primary method of curing aerospace-grade thermoset composites.

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Conference: SAMPE NEXUS 2021

Publication Date: 2021/06/29

SKU: TP21-0000000599

Pages: 12

Price: FREE