HAYNES® 556™ alloy - Haynes International, Inc.

Comparative Oxidation in Flowing Air 1800°F (980°C) for 1008 HoursMicrostructures shown are forcoupons exposed for 1008hours at 1800°F (980°C) in airflowing 7.0 feet/minute (212.0cm/minute) past the samples.Samples were descaled bycathodically charging thecoupons while they wereimmersed in a molten saltsolution. The black area shownat the top of each picturerepresents actual metal lossdue to oxidation. The dataclearly show HAYNES ® 556alloy to be superior to bothRA330 ® alloy and Type 304stainless steel as well as theother iron-base alloys shown inthe table on the previous page.45626HAYNES 556 alloyAverage Metal Affected =1.1 mils (20 µm)49258RA330 alloyAverage Metal Affected =4.3 mils (110 µm)Type 304 Stainless SteelAverage Metal Affected =8.1 mils (205 µm)Comparative Burner Rig Oxidation Resistance 1000 Hour Exposure at 1800°F (980°C)Material230 ® alloy556 alloyRA330 alloyMULTIMET ® alloyalloy 800HType 310 Stainless Steelalloy 600alloy 601*Metal Loss + Maximum Internal PenetrationOxidation Test ParametersBurner rig oxidation tests wereconducted by exposing, in arotating holder, samples 0.375inch x 2.5 inches x thickness(9.5mm x 64mm x thickness) toHAYNES ® 556 TM alloyMetal LossMils µm0.8 0.021.7 0.047.8 0.2011.8 0.3012.3 0.3113.7 0.3512.3 0.313.0 0.08**Extrapolated from 917 hoursthe products of combustion offuel oil (2 parts No. 1 and 1 partNo. 2) burned at a ratio of air tofuel of about 50:1. (Gasvelocity was about 0.3 mach).Samples were automatically10Average Metal Affected*Mils µm3.5 0.096.2 0.1611.8 0.3014.8 0.3815.3 0.3916.5 0.4217.8** 0.45**20.0 0.51removed from the gas streamevery 30 minutes and fan cooledto less than 500°F (260°C)and then reinserted into theflame tunnel.