Abstract: The bonding between carbon fiber reinforced polymers and titanium alloys is widely used in aircraft structures to achieve light weight and sufficient strength. In this study, the combination treatment of pickling, anodizing and a special resin pre-coating technology was used to improve the bonding strength of the adhesive layer/titanium alloy interface. At the same time, in order to compare the failure of the 2 joints(no reinforcement treatment and resin pre-coating treatment) after hygrothermal aging, 80 ℃/95%RH was selected as the aging environment, and the tensile test of single lap adhesive bonding was conducted after aging. The results show that the strength of the joint reinforced by resin pre-coating increases by about 52.54% without aging. After 30 days of aging, the tensile strength of the unstrengthened joints decreased by about 20.83%, while the tensile strength of the joint after the resin pre-coating treatment decreased by about 30.44%. Resin pre-coated treatment not only increased the interface bonding strength of titanium alloy plate/adhesive layer, but also played a positive role in the cohesion strength of the adhesive layer. However, compared with the initial joints, the pre-coated resin reinforced joints are more sensitive to the environment.

Key words: single-lap adhesive joint, resin pre-coating, adhesive layer failure, titanium alloy, composite
material