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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

White Rust Test 16 H08B132

Summary New Process ( %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

Questions? Thank you for your attention! 18