Authors: C Y Cui J T Guo H Q Ye
Publish Date: 2006/03/28
Volume: 41, Issue: 10, Pages: 2981-2987
Abstract
Precipitation behavior of Heusler phase Ni2AlHf in a directionally solidified DS NiAl 28Cr5Mo1Hf at alloy was examined using scanning electron microscope SEM and transmission electron microscope TEM In the ascast alloy the Ni2AlHf phase generally appeared on the NiAl/CrMo interface which degraded the NiAl/CrMo eutectic structure In the heattreated alloy the density of the intercellular Ni2AlHf phase was slightly reduced In addition the spherical Ni2AlHf phase precipitated heterogeneously in the NiAl matrix but the Ni2AlHf phase did not precipitate in the lamellar CrMo phase The precipitation behavior of the Ni2AlHf phase could be explained in terms of the interfacial energy A lattice model was also proposed to explain the NiAl↔Ni2AlHf phase transformation
Keywords: