1. Akzo Nobel Aerospace Coatings 1 Corrosion results Airbus structural systems. System 1: Conventional solvent based chromated primer + Low solids PUR topcoat System 2: Water based chromated primer + Water based epoxy topcoat. System 3: Water based chromate-free primer + Water based epoxy topcoat. CAA and TSA: 2000 h. Filiform CSP and SB: 1000 h. Filiform

2. Akzo Nobel Aerospace Coatings 2 Filiform corrosion results Boeing exterior system on different alloys and Boegel pretreatment. CF-System: High solids chromate-free epoxy-amine primer + HS PUR Topcoat. Cr.-System: High solids chromated epoxy-amine primer + HS PUR Topcoat. Boeing requirements: 720 hours 2024T3 - max. 0.125 inch / 3.2 mm. 7075T6 - max. 0.35 inch / 8.9 mm

3. Akzo Nobel Aerospace Coatings 3 Chromate-free BMS 10-72 system on different alloys. 2024T3 + Boegel 7075T6 + Boegel

4. Akzo Nobel Aerospace Coatings 4 Chromate BMS 10-72 system on different alloys. 2024T3 + Boegel 7075T6 + Boegel

5. Akzo Nobel Aerospace Coatings 5 NSS exposure to BMS 10-72 of different systems. Sample 1- 3: Chromate-free primer - topcoat system on Boegel Sample 4: Chromate primer - topcoat system on Boegel

6. Akzo Nobel Aerospace Coatings 6 NSS to BMS 10-72 (1500 h.) on 2024T3 clad: CF and Chromate primer + HS PUR topcoat. HS chromate-free primer HS chromate primer Boegel Boegel

7. Akzo Nobel Aerospace Coatings 7 NSS to BMS 10-72 (1500 h.) on 7075T6 clad: CF and Chromate primer + HS PUR topcoat. HS chromate-free primer HS chromate primerBoegel

8. Akzo Nobel Aerospace Coatings 8 Effect of primer on scribe protection in NSS. Chromate-free primer Chromate primer 1000 hours exposure of BMS 10-72 system on 2024T3 clad.

9. Akzo Nobel Aerospace Coatings 9 Conclusions.  Airbus structural primer / system corrosion requirements: -On TSA pretreatment, CF Primer technology is still slightly outside the requirements.  Boeing exterior system corrosion requirements: -On Boegel pretreatment the CF Primer – topcoat technology is able to meet the requirements.  AMS 3095 Maintenance system corrosion requirements: -The current CF primer technology is not yet able to meet the high requirements on Scotch Brite solvent cleaned bare 2024T3.  The aluminium pretreatment is a very important factor in the coating adhesion and corrosion protection of the primer / system.