Molten zinc is one of industry’s most aggressive high-temperature environments. In hot-dip galvanizing processes, chains, hooks, baskets, racks, trays, T/C protection tubes, and all sorts of other immersed components can simply dissolve away before your eyes! But you can minimize dissolution and bath contamination problems with HAYNES® 556® alloy. The 556® alloy combines resistance to molten zinc with excellent high-temperature strength, so you can design your components to weigh less and last longer
HAYNES® 556® alloy is an iron-nickel-chromium-cobalt alloy that combines effective resistance to sulfidizing, carburizing, and chlorine-bearing environments at high temperatures with good oxidation resistance, fabricability, and excellent high-temperature strength. It has also been found to resist corrosion by molten chloride salts and molten zinc.
HAYNES® 556® alloy is highly useful for service at elevated temperatures in moderately to severely corrosive environments. Applications include tubing and structural members in waste heat recuperators, super heaters, and internals in municipal and chemical waste incinerators; power plant burner buckets, air nozzles and fluidized bed combustor heat exchangers and internals; high speed furnace fans, galvanizing bath hardware and brazing fixtures; and high-temperature rotary calciners and kilns. There are also additional uses in the chemical/petrochemical process and pulp and paper industries.
Oxidation in Air - Excellent at 2000°F (1095°C)
Sulfidation - Second only to Co-base alloys
Molten Chloride Salts - Equal to alloy X
Chlorination - Very good to 1650°F (900°C)
Carburization - Equal to alloy 800H
Molten Zinc - Best Available