In situ synchrotron analysis of lattice rotations in individual grains during stress-induced martensitic transformations in a polycrystalline CuAlBe shape memory alloyActa Materialia, 59(9):3636-3645
Resume: Two synchrotron diffraction techniques, three-dimensional X-ray diffraction and Laue microdiffraction, are applied to studying the deformation behaviour of individual grains embedded in a Cu(74)Al(23)Be(3) superelastic shape memory alloy. The average lattice rotation and the intragranular heterogeneity of orientations are measured during in situ tensile tests at room temperature for four grains of mean size similar to 1 mm. During mechanical loading, all four grains rotate and the mean rotation angle increases with austenite deformation. As the martensitic transformation occurs, the rotation becomes more pronounced, and the grain orientation splits into several sub-domains: the austenite orientation varies on both sides of the martensite variant. The mean disorientation is similar to 1 degrees. Upon unloading, the sub-domains collapse and reverse rotation is observed. (C) 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Equipe: Département SI2M : Microstructures et Contraintes