Effect of Water on Peel Load of Epoxy Adhesive to Heat-Treated Aluminum

The effect of water on the interactions between heat-treated aluminum and epoxy adhesive was experimentally investigated. The peel load of aluminum-epoxy bonded specimens was measured in a 180°peel test, with water dropping onto near the peeled edge during the test. At any heat treatment temperature condition, a decrease in load occurred immediately after exposure to water, resulting in interfacial separation. At the peeled edge, some hydrogen bonds are exposed, and are thought to be broken by contact with water, resulting in a decrease in peel load.