Gas quenching in vacuum furnaces is an increasingly attractive option because it has a
low environmental impact and the least distortion of parts being treated. Whilst nitrogen is by far
the most common quenching gas, helium is a viable option where higher cooling rates are required,
particularly for carburised components. This paper explores the improvements in gas quenching
technology that allow components manufactured from standard carburising steels to be quenched
with high-pressure helium and illustrates the improvements it offers over high pressure nitrogen
quenching. As helium is an expensive rare gas, recycle systems make its use more economically
attractive. The factors that need to be taken into account when designing such systems, including
the necessity for purification, are discussed. Sources of helium and the means of delivery,
particularly in Asia, are also covered.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.