μ Phase in a nickel base directionally solidified alloy

Abstract

Scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray diffraction (XRD) were employed to study the μ phase in a directionally solidified experimental nickel base alloy. It was observed that the μ phase distribute at interdendritic area and precipitate mainly from the γ′ phase in this experimental alloy. Orientation relationship between the γ′ and the μ phase was found as (111)γ′ || (0001)μ and 〈1̄10〉γ′ || 〈112̄0〉μ. Detrimental effect of the μ phase on oxidation resistance of the alloys was also found. ©2005 The Japan Institute of Metals.