Some effects of trace elements in reducing creep performance of high–strength superalloys

Abstract

In the high–strength superalloys used for ‘hot-end’ components in gas turbine engines, small amounts of elements with low melting points can have a seriously detrimental effect on high–temperature performance. Some of the more recent work carried out to define harmful levels of trace element content and to develop an understanding of the mechanisms involved is briefly reviewed in this paper. The emphasis is on results available for cast alloys; the problem of gaseous impurities in recycled material is also considered. The implications for the specification and control of trace element content are briefly discussed.

MST/161