Berlin 2005 – wissenschaftliches Programm
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M: Metallphysik
M 32: Poster TU B (Symposium Tomographic Methods in Materials Research M-32.32-55)
M 32.30: Poster
Montag, 7. März 2005, 14:30–16:30, Poster TU B
Microstructure of Fe2Re (Re=Tb, Nd) spherical alloy produced by containerless solidification in drop tube — •Shumpei Ozawa1,2, Kazuhiko Kuribayashi1, and Dieter Herlach2 — 1Institute of Space and Astronautical Science, 3-1-1 Yoshinodai, Sagamihara, 229-8510, JAPAN — 2Institute of Space Simulation, German Aerospace Center, 51170 Cologne, GERMANY
Fe2TbxNd1-x alloy were containerlessly solidified in a drop tube. Droplets of various diameters were formed and collected at the bottom of the drop tube. The microstructures of the Fe2Tb samples consist of two regions. One is properitectic Fe3Re phase in the Fe2Tb matrix and the other is primary Fe2Tb dendritic grains. The region that consists of Fe2Tb dendrite expands due to the enhancement of the undercooling and cooling rate with decreasing the sample diameter. In the Fe2Tb0.5Nd0.5 samples, the Fe3Re phase crystallized from the melt directly. The Fe2Re phase is peritectically formed from Fe3Tb and liquid phases. The further improvement in the solidification conditions such as the ejection gas pressure and temperature of the molten metals together with the composition modifications should be favorable to increase the undercooling level for the direct crystallization of the Fe2Re phase. This will be a challenge to produce the Fe2Nd Laves phase directly from the undercooled melt, which has been theoretically predicted to exhibit the highest magnetostrictive strain.