Title: Injection-Based Repair of Delaminated Composites Using a Low-Viscosity, Room Temperature Gel Epoxy Resin

Authors: Lu Han, Ken Wong, Hideki Yamatomo, Masaya Kotaki

DOI:

Abstract: A two-part epoxy-amine injection repair resin was developed to enable deep infiltration into microcracks and delaminated regions through its ultra-low viscosity, ≤95 mPa·s at 21°C. The resin gels at ambient temperature within 12 hours and cures at temperature as low as 71 °C, supporting practical field-level composite repair. Composites laminates fabricated with the resin matrix confirmed its inherent mechanical capability. Mechanical performance of repaired laminates was quantitatively evaluated against undamaged and damaged baselines across multiple aerospace epoxy and benzoxazine prepreg systems using edge and center injection methods. Strength recovery ranged from 86% to 103%. These results demonstrate that the low-viscosity, low-temperature-cure resin provides effective structural restoration for delaminated composite components.

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Conference: SAMPE 2026

Publication Date: 2026/04/27

SKU: 119

Pages: 12

Price: $24.00