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Low temperature a/b nanotwins in Ni₅₀Mn_25+xGa_25-x Heusler alloys.

ABSTRACT: We have found low temperature a/b nanotwins having (110) twinning plane in a five-layered modulated martensite phase of Ni₅₀Mn_25+xGa_25-x (at. %) Heusler alloys and identified the particular region in phase diagram where the nanotwinning occurs. Evolution of the structure with decreasing temperature was studied by X-ray diffraction using single crystals exhibiting magnetic shape memory effect. The merging of (400) and (040) lines upon cooling for 2.6?2. As the nanotwinning distorts the relation between the crystal lattice and the X-ray diffraction pattern, it should be taken into consideration in structural studies of Ni-Mn-Ga Heusler alloys.

SUBMITTER: Straka L

PROVIDER: S-EPMC6085376 | biostudies-literature | 2018 Aug

REPOSITORIES: biostudies-literature

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Low temperature a/b nanotwins in Ni50Mn25+xGa25-x Heusler alloys.

Straka L L Drahokoupil J J Veřtát P P Zelený M M Kopeček J J Sozinov A A Heczko O O

Scientific reports 20180809 1

We have found low temperature a/b nanotwins having (110) twinning plane in a five-layered modulated martensite phase of Ni50Mn25+xGa25-x (at. %) Heusler alloys and identified the particular region in phase diagram where the nanotwinning occurs. Evolution of the structure with decreasing temperature was studied by X-ray diffraction using single crystals exhibiting magnetic shape memory effect. The merging of (400) and (040) lines upon cooling for 2.6 < x < 3.5 ind ...[more]

PMID: 30093683

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