Effect of surface impurities on peel strength in adhesively bonded joints

The performance of adhesive bonding is significantly affected by the quality of surface preparation. Contaminants, especially residual surfactants from cleaning processes, can greatly diminish the strength of bonded joints. This study examines how surfactant contamination impacts the peel strength of joints formed between aluminum substrates and a silicone-based adhesive. A peel test was conducted on joints with varying levels of contamination-0, 10, and 20 sprays. Results revealed a progressive reduction in peel strength and a transition from cohesive to interfacial failure with increased contamination. The findings were corroborated by numerical simulations using the Finite Element Method (FEM) implemented in Abaqus.