The overall objective of this dissertation is to i) illustrate the effectiveness of commercial TCP conversion coatings on wrought aluminum alloy and ii) apply commonly used surface treatments to an additively manufactured aluminum alloy. First, two TCP coatings are studied on wrought aluminum alloy AA2024-T3. One of the TCP coatings is pretreated by a degrease step followed by deoxidation before applying the coating. The other TCP coating involves a simplified pretreatment which does not require the deoxidation step. The formation and structure of the conversion coatings are compared using analytical techniques. Then, the corrosion behavior was evaluated using electrochemical methods and accelerated degradation testing. A second aim of the research was to investigate the material properties and electrochemical behavior of aluminum alloy, AlSi10Mg, prepared by additive manufacturing using selective laser melting (SLM). Two studies of corrosion protective coatings on SLM AlSi10Mg are presented: i) the TCP conversion coating and ii) Type II (sulfuric acid) anodization.
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