Investigation of Integrated Coating System for Corrosion Protection

摘要

This report details the coating systems developed under STTR contract for topic AFO1-018. Coating systems comprising an inhibitor-doped layer-by-layer (LEL) assembly basecoat and a dense organically modified silicate (Ormosil) topcoat were investigated as corrosion-resistant coatings for 2024-T3 aluminum alloy. Neither the LBL nor the Ormosil materials were found to provide adequate corrosion protection for the underlying metal. A combination of the two coating methods was found to produce a synergistic enhancement in corrosion-resistance characteristics. Incorporation of an active corrosion inhibitor into the LEL coating was also found to improve corrosion-resistance properties. Zincate solutions were found to remove LBL/Ormosil coatings 'on demand' from the aluminum-alloy substrate. All objectives set forth in the original Phase 1 project have been accomplished successfully, resulting in the development of an environmentally compliant protective coating that incorporates active corrosion inhibitors and that can be removed readily when needed.