Double cantilever beam testing of repaired carbon fibre composites

Low-temperature cure adhesive systems have been evaluated for repair of composites. Pre-cracked DCB fracture toughness specimens were repaired using an ethylcyanoacrylate (ECA) system and an epoxy-based system cured with 4,4'-methylene-bis(aminocyclohexane) (PACM), and the post-repair fracture toughness measured. The results showed that both groups of repaired specimens exhibited higher GI, than the original specimens. However, the EGA-repaired specimens showed a greater tendency to fracture in a stick-slip fashion compared to specimens repaired with epoxy. (C) 2000 Elsevier Science Ltd. All rights reserved.