Repair of Damaged Fiber Reinforced Polymer Composites with Cold Spray

Abstract

The promising structural properties of fiber-reinforced polymer composites make them widely popular in the energy, automotive, defense, and aerospace industries. One of the most challenging limitations associated with the use of composites in the above applications is the maintenance and repair protocols. In this study, a novel cold spray approach is introduced as an efficient alternative for the structural repair of fiber composites. Damages in the form of circular tapered holes are created in glass fiber-reinforced polymer (GFRP) composite substrates using a conventional drilling process. The in-lab created damages are repaired by cold spray with thermoplastic (nylon 6) and thermoset (polyester epoxy resin, PER) materials. The fundamental adhesion mechanisms are investigated through microstructural observations, which point to adiabatic shear instability due to the occurrence of severe plastic deformation as a governing factor. Microstructural examinations also suggest that no significant fiber damage or surface degradation occurs after the repair by cold spray. Mechanical tests performed on neat, damaged, and repaired composites reveal the partial recovery of structural performance and load-bearing capacity after cold spray repair. Results obtained in this work highlight cold spray as a promising alternative technique for onsite structural repair of composite structures with minimal pre/post-processing requirements.

Cold Spray Deposition of Nylon-6 on Glass Fiber-Reinforced Composites

“…The research leading to this article expanded the existing knowledge of cold spray as an additive manufacturing process for coating and repair of fiber-reinforced polymers (e.g., see ref for more details regarding the potential application of polymer cold spray as a composite repair process). Comparing the results of the present work to the existing literature, several improvements and novel insights were identified.…”

Feasibility of Repairing Concrete with Ultra-High Molecular Weight Polyethylene Fiber Cloth: A Comprehensive Literature Review

“…Excessive cracking increases the possibility of structural damage, making innovative solutions for repair and reinforcement necessary [3][4][5][6][7][8]. Traditional repair methods are limited in their ability to meet the requirements of modern engineering practices, prompting the search for novel approaches to address the challenges posed by deteriorating concrete [9][10][11][12][13].…”