New aluminium cast alloys have significantly increased ductile properties, compared to conventional aluminium die-cast components so that a new field of application could be opened up. In addition to the welding of aluminium, adhesive bonding of complex and thin-walled die-cast components provide interesting economic perspectives. Careful surface treatments to remove die casting mold release agents from the surfaces are inevitable for a high long-term durability of the adhesive bond. Due to the lack of knowledge regarding the effect of the release agents on the quality of an adhesive bond, it is necessary to gain a better understanding of the diffusion and migration behavior of release agents in the surface area. In this study, four types of surface treatment processes - conventional wet-chemical process and conversion coating, laser ablation and plasma pre-treatment - have been investigated with regard to surface cleaning. Single lap shear tests were performed to quantify the bond strengths and durability after having been subjected to the various surface treatments. Quantitative detection of the release agent on the surface was measured by using methods of micro analysis including the EPMA. In addition, emphasis was placed on the investigation of diffusion and migration paths of release agents and their dependence on treatment and storage conditions, especially under the influence of time.
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