Surface Cleaning and Pretreatment for Additive Manufacturing and Aerospace Materials Utilizing Environmentally Safe Aqueous Chemicals

Surface preparation for Aerospace and Additive Manufacturing (AM) materials is critical for manufacturing processes and for final performance and long-term functionality. Data for environmentally safe aqueous surface cleaning, deoxidizing and preparation processes will be presented. Prior art has been complicated by the difficulty in removing the oxides and residues associated with material processing and/or a heat treatment process. Surface cleaning using hazardous materials such as hydrofluoric or chromic acids has been used. These chemicals pose extreme hazards for operators and pose liability risks for the companies using the processes and those disposing of the waste. Application of the processes on Aluminum, Titanium, Inconel, and Composite aerospace materials has been demonstrated. Substrate surfaces have exhibited water break free conditions without etching. Etching to remove surface deformation due to fabrication has also been demonstrated. The process has been performed using immersion, spray and hand application. Deoxidizing of Additive Manufacturing powders reduces or eliminates oxide inclusion in the final article providing a homogeneous material with reproducible mechanical properties. Glass and ceramic materials have also been deoxidized to provide clear and bondable surfaces. The family of cleaners is tailorable for specific application on Additive Manufacturing, bonding, chemical film, anodize, welding, joining, and painting processes. A variety of surface coatings (including Anodize and Alodine^® 1200S) have been applied with excellent adhesion and corrosion resistance. These processes are operator safe and allow for disposal into municipal waste systems.