IMI 834 is a recently developed alloy, for aeroengine applications up to 863K. These alloys exhibited the best high temperature properties of all the near #alpha# alloys. This paper presents exploratory research work conducted for further enhancement of high temperature capabilities of IMI 834 by microalloying.Pancakes of IMI 834 alloy with microadditions such as tantalum, bismuth, iron, cobalt, nickel, boron and misch metal (Mm) were prepared by vacuum arc melting. These alloys were evaluated for strength and creep at 873 K for varieties of microstructures.The results indicate that alloys containing eutectoid formers (iron, cobalt, nickel, and bismuth) show the lower strength whereas alloys containing tantalum, boron, Mm exhibit higher strength than the base IMI 834. Eutectoid formers, in general, have adverse effect on the creep properties as well. Alloying additions that are isomorphous in titanium such as tantalum have not resulted in the improvement of the creep properties. An assessment of creep properties of the alloys containing boron and Mm indicates that creep properties of these alloys are relatively insensititive to cooling rates. This allows optimisation of other properties such as yield strength by choice of an appropriate beat treatment without deterioration of creep properties.
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