Industry is constantly searching for improved materials for use in highly demanding applications. The materials chosen must withstand a wide range of temperatures and extended exposure in aggressive environments, including hydrogen gas. Because of the risk of catastrophe if brittle failure occurs, careful material selection is imperative. Austenitic stainless steels may be a likely choice for hydrogen service because their behavior in high pressure hydrogen ranges from no apparent damage to relevant, but generally small ductility loss (13). Because of this Variation in behavior, a single category cannot be established to encompass all austenitic steels and studies must be performed on each type of steel to determine its behavior under specific circumstances. Two steels being currently under consideration for use in hydrogen are Armco 21-6-9 and Tenelon, both are fully austenitic stainless steels which may be used over a wide range of temperatures, including service at liquid nitrogen temperature. / Master of Science / incomplete_metadata