Volume 6, Issue 10 (November 2009)
Promoted Ignition-Combustion Behavior of Cobalt and Nickel Alloys in Oxygen-Enriched Atmospheres
Promoted ignition-combustion behavior has been used to describe a situation in which a substance with low oxygen compatibility ignites and supports the combustion of a more combustion-resistant material. Previous work has been reported on the investigation of this phenomenon as it relates to carbon steel, stainless steels, and a number of significant engineering alloys in the nickel, cobalt, and copper families. Reported in this paper are the results of promoted ignition-combustion tests of three cobalt based alloys in oxygen-enriched atmospheres at pressures ranging from 2.86 to 34.5 MPa. Included in the test program were Stellite 6, a commonly used hard facing alloy and two high strength cobalt alloys—MP35N and Elgiloy. Also reported in this paper are the results of promoted ignition-combustion tests of four nickel based alloys in oxygen-enriched atmospheres at pressures up to 34.5 MPa. Nickel alloys evaluated in the program included Hastelloys B-3 and W, RA 330, and a cast variant of the Hastelloy C type, CW6M. Hastelloy B-3 and CW6M are used in chemical process industry applications where corrosion is of concern. RA 330 is a significant elevated temperature alloy. Hastelloy W is a filler metal used for dissimilar metal welds.