Stress-Assisted Removal of Conjugation Boundaries in Non-Modulated Ni–Mn–Ga by Coordinated Secondary Twinning

Authors

B. Muntifering, Boise State University
L. Kovarik, Pacific Northwest National Laboratory
N. D. Browning, Pacific Northwest National Laboratory
R. C. Pond, University of Exeter
W. B. Knowlton, Boise State UniversityFollow
P. Müllner, Boise State UniversityFollow

Document Type

Article

Publication Date

1-2016

Abstract

Observations are presented, obtained by in situ straining and conventional TEM, of a transformation mechanism by coordinated secondary twinning predicted by Mullner and King. The material studied is the martensitic phase of a non-modulated Ni–Mn–Ga alloy, which exhibits a microstructure comprising domains of lamellar matrix/twin composites. Straining these specimens induced lamellar domains to transform into their conjugate counterparts. In this process, secondary twinning generates a change of misorientation between the matrix and twin lamellae of the initial domain by nearly 23°. The orientation evolves over a region behind the transformation front about 100 nm in extent.

Publication Information

Muntifering, B.; Kovarik, L.; Browning, N. D.; Pond, R. C.; Knowlton, W. B.; and Müllner, P.. (2016). "Stress-Assisted Removal of Conjugation Boundaries in Non-Modulated Ni–Mn–Ga by Coordinated Secondary Twinning". Journal of Materials Science, 51(1), 457-466. https://doi.org/10.1007/s10853-015-9236-1