|Number of page(s)||5|
|Section||Principles, Simulations, Materials: Background|
|Published online||01 September 2009|
Structure development in Co38Ni33Al29 ferromagnetic shape memory alloyJaromír Kopeček, Silvie Sedláková-Ignácová, Karel Jurek, Markéta Jarošová, Jan Drahokoupil, Petr Šittner and Václav Novák
Institute of Physics AS CR, v.v.i., 182 21 Praha, Czech Republic
Published online: 1 September 2009
In the present study, a set of the directionally solidified samples from ferromagnetic shape memory alloy with the nominal composition Co38Ni33Al29 was prepared using the Bridgman method. It is shown that various growth rates result in various solidification structures of the crystals, mainly in different ratios of the disordered phase γ cobalt solid solution and the ordered phase β - B2 (Co,Ni)Al. This ratio has the fundamental effect on the temperature of the martensitic phase transition. The results are compared with the structure of samples prepared by the floating zone method. The structures of samples prepared with the different growth rate were studied by metallography, SEM, EDX, and EBSD methods. The samples without high-angle grain boundaries were cut from the prepared crystals for the mechanical testing.
© Owned by the authors, published by EDP Sciences 2009