1. A Comparative Study of the 0.05Al Process October 2, 2012

2. Background Al for broadband Si reactivity control H. Guttman and P. Niessen, 1975 M. Pierre, 1975 Commercialization failure of Polygalva, 1979 Al-compatible flux (G-flux) US Patent US 7,811,389 B2, 2010 Commercial production of 12Al coating 2

3. Parts Steel Parts (2982 kg in total) 0.04% - 0.28% Effective Si 3

4. Baths, Centrifuge and Products Baths (2400 kg each) Bath A: 0.039%Al Bath B: 0.051%Al Bath H: 0.005%Al 4

5. Pretreatments 5 Degrease 20 minutesPickle 20 minutesRinse 1 minute Flux 1 minuteDry 120ºC 15 minutes

6. Coating Thickness (4 minutes) 6 450ºC (842ºF), 4 minutes

7. Coating Thickness (Prior Study) 7 440ºC (824ºF), 8 minutes

8. Coating Thickness (10 minutes) 8 450ºC (842ºF), 10 minutes

9. Coating Adhesion (Part e3) 9 Bath B, 10 min Bath B, 4 minBath H, 4 min Bath A, 4 min

10. Microstructure (Part e3, 0.21%Si) 10 Bath B, 10 min Bath B, 4 minBath H, 4 min Bath A, 4 min

11. ζ δ Flaked-off Coating 11 Bath B, 10 min Bath H, 4 min Bath A, 4 min

12. Coating Adhesion (Part a) 12 Bath H, 4 min Bath B, 10 min Bath A, 4 min

13. Microstructure (Part a, 0.24%Si) 13 Bath H, 4 min Bath B, 10 min Bath A, 4 min

14. Zinc Consumption 14 Bath ABBath H Coating2.48%2.97% Dross4.81%4.11% Ash1.38%1.35% Total8.67%8.43%

15. Drainage (Part k) 15 The amount of accumulation at the bottom of Part k: BathW (g)W (lb) H3.90.0086 A3.00.0066 B2.90.0064 Students test indicated that there were significant differences between Baths H and AB, whereas there was no significant difference between Baths A and B.

16. White Rust Test 16 H08B132

17. Summary New Process (0.04-0.05%Al) vs. HDG Al-compatible flux (G-Flux) Brighter, shinier and thinner coating Improved coating adhesion Slightly better drainage Slightly more dross but same amount of ash Less visible oxide skin More localized white rust Slightly shorter kettle life 17

18. Questions? Thank you for your attention! 18