A Study on the Effects of Surface Energy and Topography on the Adhesive Bonding of Aluminum Alloy

Abstract

The bonding properties of adhesives are mainly affected by surface roughness, topography and chemical adsorption. In this paper, we studied the effects of surface pretreatment of Al 2024-T3 (bare) in terms of surface roughness, topography and surface free energy. Surface pre-treatment included solvent cleaning, FPL etching, PAA and CAA treatment. The surface energy and roughness of the aluminum surface were significantly increased by the anodizing treatment. Single lap shear and fatigue tests were performed to investigate bonding properties and durability. The evaluation revealed that the surface energy and surface roughness resulting from the aluminum surface treatment had a significant impact on bonding properties and durability. PAA treated surfaces had the highest bonding strength, and CAA treated surfaces had superior bonding retention performance in hot water or salt spray environments. The results of the fatigue test most clearly demonstrated how the surface pretreatment of the aluminum alloy differently affected bonding performance.