Improvement of aluminum lithium alloy adhesion performance based on sandblasting techniques

In this study, the aluminum lithium alloy (Al-Li alloy) sheets were subjected to sandblasting treatments using different parameters, and the specimens then were bonded as single lap joints with FM94 adhesive. The surface morphology, surface free energy, and shear strength of the specimens were investigated and analyzed, to comprehensively study how sandblasting can enhance the shear strength of Al-Li alloy joints. The results show that an increase in sandblasting pressure and abrasive size leads to an increase in surface roughness, which contributes to the surface wettability and adhesion performance of the substrates. The bonding properties between Al-Li alloy and FM94 adhesive can be greatly improved by sandblasting treatment, a moderate surface roughness is found to yield better wettability and stronger shear strength.