Neutron diffraction study on crystal structure and phase transformation in Ni-Mn-Ga ferromagnetic shape memory alloys

Cong, D. Y. (författare)

Wang, Y. D. (författare)

Xu, J. Z. (författare)

Zuo, L. (författare)

Zetterstroem, P. (författare): Stockholms universitet,Avdelningen för strukturkemi

Delaplane, R. (författare): Uppsala universitet,Neutronforskningslaboratoriet i Studsvik

(creator_code:org_t)

2012-03-01
2007
Engelska.
Ingår i: Powder Diffraction. - : Cambridge University Press (CUP). - 0885-7156 .- 1945-7413. ; 22:4, s. 307-311

Relaterad länk:: https://urn.kb.se/re...; visa fler...; https://doi.org/10.1...; https://urn.kb.se/re...; visa färre...

Abstract Ämnesord

Stäng

Crystal structure and phase transformation behaviors in two Ni-Mn-Ga ferromagnetic shape memory alloys (FSMAs) with compositions of Ni48Mn30Ga22 and Ni53Mn25Ga22 (at. %) as a function of temperature were investigated by in situ neutron diffraction experiments. Neutron diffraction technique proves to be highly efficient in characterizing structural transformation in Ni-Mn-Ga FSMAs, which consist of nearby elements in the periodic table. Our neutron results show that Ni48Mn30Ga22 has a cubic, L-21 Heusler structure from 373 to 293 K. Its crystal structure changes into a seven-layered orthorhombic martensitic structure when cooled to 243 K, and no further transformation is observed upon cooling to 19 K. Neutron diffraction results also show that Ni53Mn25Ga22 has a tetragonal 14/mmm martensitic structure from 20 to 403 K. A pre-transformation around room temperature is observed from an abrupt jump in unit-cell volume of Ni53Mn25Ga22, which corresponds with an endothermic peak detected in a heated DSC curve.

Av författaren/redakt...: Cong, D. Y.; Wang, Y. D.; Xu, J. Z.; Zuo, L.; Zetterstroem, P.; Delaplane, R.

Om ämnet

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.