A4 Conference proceedings

4D STUDY OF STRAIN GRADIENTS EVOLUTION IN TWINNED NiMnGa SINGLE CRYSTALS UNDER MAGNETIC FIELD


Publication Details

Authors: Barabash R, Xu R, Barabash OM, Sozinov A

Publication year: 2014

Language: English

Title of parent publication: Oak Ridge National Lab.(ORNL), Oak Ridge, TN (United States), 2014. 35th Risoe international meeting, Roskilde, Denmark, 20140901, 20140905

JUFO level of this publication: 0

Open Access: Not an Open Access publication


Abstract

Time-resolved 3D X-ray microscopy with a submicron beam size was used to follow the evolution of strains in off-stoichiometric NiMnGa twinned crystals near type I (hard) twin boundary under magnetic field. Laminate A/B microstructure was revealed near the twin boundaries in A variant. Large strain gradients are observed in the C variant in the immediate vicinity of the type I twin boundary: the lattice is under large tensile strains ~0.4% along the c- axes within first micron. Distinct a and b lattice parameter evolution with temperature and magnetic field is demonstrated. In an applied magnetic field the strain field was observed at larger distances from the twin boundary and becomes more complex. Stochastic twin boundary motion was observed after the magnetic field reaches a certain critical value.


Last updated on 2019-05-01 at 15:34