The preparation of oriented samples of ferromagnetic shape memory alloy CoNiAl

0343310 - FZÚ 2011 RIV GB eng J - Journal Article
Kopeček, Jaromír - Jurek, Karel - Jarošová, Markéta - Drahokoupil, Jan - Sedláková, Silvia - Šittner, Petr - Novák, Václav
The preparation of oriented samples of ferromagnetic shape memory alloy CoNiAl.
IOP Conference Series: Materials Science and Engineering. Roč. 7, č. 1 (2010), 012013/1-012013/8. ISSN 1757-8981.
[European Workshop on Modern Developments and Applications in Microbeam Analysis /11./. Gdansk, 10.05.2009-14.05.2009]
R&D Projects: GA AV ČR IAA200100902; GA AV ČR(CZ) IAA200100627; GA ČR(CZ) GA101/09/0702
Institutional research plan: CEZ:AV0Z10100520; CEZ:AV0Z10100521
Keywords : shape memory alloys * cobalt * metallography * crystal growth * scanning electron microscopy
Subject RIV: BM - Solid Matter Physics ; Magnetism

In the present study, the set of the directionally solidified samples from alloy with the nominal composition Co38Ni33Al29 were prepared using the Bridgman and the floating zone method. Various growth rates results in various solidification structures, mainly different ratio of the disordered phase γ-cobalt solid solution and the ordered phase (β-B2 (Co,Ni)Al. The ratio has the fundamental effect on the temperature of the martensitic phase transition. This evolution of the samples structure was studied by metallography, SEM, EPMA and EBSD methods. The results are discussed in the frame of decomposition kinetics of this ternary alloy. The samples without high-angle grain boundaries, i.e., single-crystals, can be cut from the prepared directional grown ingots and used to examine mechanical properties.
Permanent Link: http://hdl.handle.net/11104/0185818