Application and evaluation of environmentally compliant spray-coated ormosil films as corrosion resistant treatments for aluminum 2024-T3

An epoxide modified silicate sol–gel film spray coated on an aluminum alloy 2024-T3 coupon was demonstrated to provide exceptional barrier and corrosion protection when compared to chromate-based surface treatments. Surface characterization indicated that the applied film was 2.2 μm thick and crack free. Potentiodynamic evaluation revealed that the film provided a continuous barrier of protection over a broad potential range. Comparison with standard Alodine-1200 type surface treatment indicated several orders of magnitude improvement in barrier protection and enhanced protection under accelerated corrosion test.