Abstract
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In-situ neutron diffraction during cyclic tension-compression loading (þ3.5% to 2.8%) of a
17Mn-3Al-2Si-1Ni-0.06C steel that exhibits concurrent transformation and twinning -induced plasticity effects indicated a significant contribution of intragranular back stresses to the observed Bauschinger effect. Rietveld analysis revealed a higher rate of martensitic transformation during tension compared to compression. Throughout cycling, a0-martensite exhibited the highest phase
strains such that it bears an increasing portion of the macroscopic load as its weight fraction
evolves. On the other hand, the e-martensite strain remained compressive as it accommodated most of the internal strains caused by the shape misfit associated with the c!e and/or e!a0 transformations.