Strengthening the Substrates of Wood Single Lap Joints Using a Novel Hot-Melt Film Adhesive to Mitigate Delamination

Aiton) substrates to improve stress wave propagation. A finite element elastic model was developed to analyse stress distributions and explain the superior performance of hybrid joints. Results revealed that the thermoplastic interlayer delayed delamination onset and increased energy absorption, while hybrid configurations achieved more uniform stress distributions and significantly higher strengths under dynamic loading. The most effective configuration, the hybrid joint under impact conditions, represents a strength improvement of approximately 84% of the peak load compared to the pine reference joints. Overall, introducing a thermoplastic interlayer offers an efficient and lightweight strategy to enhance the toughness and reliability of wood joints exposed to variable loading conditions.