HAYNES® 214® alloy

HAYNES® 214® alloy provides resistance to oxidation at temperatures of 1750°F (955°C) and above that is virtually unmatched by any other wrought heat-resistant alloy. It can be used for long-term continuous exposure to combustion gases or air at temperatures up to 2300°F (1260°C), and, for shorter term exposures, it can be used at even higher temperatures. Useful short-term oxidation resistance has even been demonstrated at temperatures as high as 2400°F (1315°C).

Metallographic Technique used for Evaluating Environmental Tests

Comparative Oxidation in Flowing Air 2100°F (1150°C)

Microstructures shown are for coupons exposed for 1008 hours at 2100°F (1150°C) in air flowing at 7.0 feet/minute (213.4 cm/minute) past the samples. Samples were descaled by cathodically charging the coupons while they were immersed in a molten salt solution. The black area shown at the top of each picture represents actual metal loss due to oxidation. The data clearly show HAYNES® 214® alloy is only slightly affected by the exposure, while other nickel-chromium alloys, such as alloys 600 and 601, and iron-nickel-chromium alloys, such as RA330® alloy, all exhibit significantly more oxidation damage. Of particular importance is the almost total absence of internal attack for the 214 alloy. This contrasts markedly with the very substantial amount of internal attack evidenced by the alloy 601 and RA330 alloy tests coupons. The nature of this internal attack, as illustrated by the photomicrographs, is common for alloys containing 1-2% aluminum or silicon. Such levels of these elements do promote chromium oxide scale adherence, but do not afford improved resistance to oxide penetration below the scale.

HAYNES® 214® alloy
Average Metal Affected
= 0.5 mils (13 µm)

Alloy 600
Average Metal Affected
=4.8 mils (122µm)

Alloy 601
Average Metal Affected
=6.5 mils (165 µm)

RA330 alloy
Average Metal Affected
=8.7 mils (221 µm)

Oxidation Test Paramerters

Burner rig oxidation tests were conducted by exposing, in a rotating holder, samples 0.375 inch x 2.5 inches x thickness (9.5mm x 64mm x thickness) to the products of combustion of fuel oil (2 parts No. 1 and 1 part No. 2) burned at a ratio of air to fuel of about 50:1. (Gas velocity was about 0.3 mach). Samples were automatically removed from the gas stream every 30 minutes and fan cooled to less than 500°F (260°C) and then reinserted into the flame tunnel.

Comparative Burner Rig Oxidation Resistance at 1800°F (980°C)/1000 Hours

(Black areas of micros indicates actual metal loss)

Comparative Burner Rig Oxidation Resistance at 2000°F (1095°C)/500 Hours

Water Vapor