Effects of cerium on the microstructures and grain sizes of cast TiAl alloys

Authors
Citation
Cm. Liu et al., Effects of cerium on the microstructures and grain sizes of cast TiAl alloys, J MATER SCI, 35(4), 2000, pp. 975-980
Citations number
10
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science","Material Science & Engineering
Journal title
JOURNAL OF MATERIALS SCIENCE
ISSN journal
00222461 → ACNP
Volume
35
Issue
4
Year of publication
2000
Pages
975 - 980
Database
ISI
SICI code
0022-2461(200002)35:4<975:EOCOTM>2.0.ZU;2-Z
Abstract
The rare earth element cerium (Ce) was added to cast binary Ti-44 at.% Al a lloys by arc melting in the range of 0.05 to 0.3 atomic percent. It was obs erved that the as-cast structures of the ingots consisted of the usual thre e zones of fine equiaxed grains near the mould wall, columnar grains growin g away from the mould wall and coarse equiaxed grains near the center. Ce g reatly promoted the growth of columnar grains and reduced their diameters. The ingots were subsequently heat treated to obtain well-defined fully lame llar structures. The material containing no rare earth displayed large equi axed lamellar colonies of average size of > 1400 mu m; the material with 0. 05 at.% addition of Ce consisted of lamellar colonies of as fine as similar to 440 mu m. The finest grain size of this material was 320 mu m at the to p position in the ingot. (C) 2000 Kluwer Academic Publishers.