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Volume 5, Issue 5
Res. Rev. J Mat. Sci. 2017
ISSN: 2321-6212
Advanced Materials 2017
September 07-08, 2017
September 07-08, 2017 | Edinburgh, Scotland
Advanced materials & Processing
11
th
International Conference on
Thermodynamics and kinetics of competitive crystallization pathways during devitrification ofAl-Smamorphous
alloys
R.E. Napolitano
1
, S.H. Zhou
2
, F. Meng
2
, W. Wang
2
, P. Ray
2
, M.J. Kramer
2
1
Iowa State University, USA
2
Ames Laboratory, USA
A
morphous alloys of Al-Sm exhibit competitive devitrification behavior upon reheating, involving competition between
multiple metastable phases. These include large-unit-cell phases with cubic, hexagonal, and tetragonal symmetry, along with
more conventional stable and metastable compounds of the AlxSm variety. Phase selection during crystallization is strongly path
dependent, owing to effects of non-crystalline ordering and the role of diffusion and chemical partitioning in the morphological
dynamics. In this work, devitrification kinetics are investigated and quantified using high energy X-ray diffraction, thermal analysis,
and electron microscopy. Measurements are related to system thermodynamics in the highly driven regime highlighting principles of
selection. Growth mechanisms are investigated in detail, with particular attention to chemical partitioning associated with the initial
crystallization front. Implications with respect to other Al-RE (rare-earth) systems are also discussed. This work was supported by
the U.S. Department of Energy, Office of Basic Energy Science, Division of Materials Sciences and Engineering. The research was
performed at the Ames Laboratory, operated for the U.S. Department of Energy by Iowa State University under Contract No. DE-
AC02-07CH11358.
ren1@iastate.eduRes. Rev. J Mat. Sci. 2017, 5:5
DOI: 10.4172/2321-6212-C1-006