Fraunhofer-Gesellschaft

Publica

Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

Analysis of structural and functional properties of Ni50Mn30Ga20 after plastic deformation

 
: Böhm, A.; Naumann, G.; Drossel, W.-G.; Neugebauer, Reimund

Ruhr-Universität, Institut für Werkstoffe-Werkstoffwissenschaft, Bochum:
7th European Symposium on Martensitic Transformations and Shape Memory Alloys 2006 : ESOMAT 2006, held in Bochum, Germany, September 10th to 15th, 2006
Bochum, 2006
pp.133
European Symposium on Martensitic Transformations (ESOMAT) <7, 2006, Bochum>
English
Conference Paper
Fraunhofer IWU ()
shape memory alloy; NiMnGa; martensitic transformation; compression test; hot-rolling

Abstract
Some NiMnGa single crystals exhibit a magnetic-field-induced strain (MFIS) in the low temperature martensitic phase. In order to obtain such MFIS in polycrystalline samples, the use of textured samples is most promising. The paper describes experimental results of compression tests of a Ni50Mn30Ga20 alloy at high temperatures up to 1000 °C which show that the magnetic shape memory alloy (MSMA) exhibits a good plastic deformation behavior above the ordering temperature in the B2 (CsCl) structure. Flow curves were obtained for various strain rates. Experiments using the hot rolling process were successful. The results show that it is possible to obtain pre-orientation of the twinned martensitic structure. The cast and hot-rolled specimens were characterized by differential scanning calorimetry, X-ray diffraction and optical microscopy using differential interference contrast. The changes in structural properties of specimens after plastic deformation are presented and discussed.

 

Some NiMnGa single crystals exhibit a magnetic-field-induced strain (MFIS) in the low temperature martensitic phase. In order to obtain such MFIS in polycrystalline samples, the use of textured samples is most promising. The paper describes experimental results of compression tests of a Ni50Mn30Ga20 alloy at high temperatures up to 1000 °C which show that the magnetic shape memory alloy (MSMA) exhibits a good plastic deformation behavior above the ordering temperature in the B2 (CsCl) structure. Flow curves were obtained for various strain rates. Experiments using the hot rolling process were successful. The results show that it is possible to obtain pre-orientation of the twinned martensitic structure. The cast and hot-rolled specimens were characterized by differential scanning calorimetry, X-ray diffraction and optical microscopy using differential interference contrast. The changes in structural properties of specimens after plastic deformation are presented and discussed.

: http://publica.fraunhofer.de/documents/N-52121.html