Combined near- and far-field high-energy diffraction microscopy dataset for Ti-7Al tensile specimen elastically loaded in situ

Abstract

High-energy diffraction microscopy (HEDM) constitutes a suite of combined X-ray characterization methods, which hold the unique advantage of illuminating the microstructure and micromechanical state of a material during concurrent in situ mechanical deformation. The data generated from HEDM experiments provides a heretofore unrealized opportunity to validate meso-scale modeling techniques, such as crystal plasticity finite element modeling (CPFEM), by explicitly testing the accuracy of these models at the length scales where the models predict their response. Combining HEDM methods with in situ loading under known and controlled boundary conditions represents a significant challenge, inspiring the recent development of a new high-precision rotation and axial motion system for simultaneously rotating and axially loading a sample. In this paper, we describe the initial HEDM dataset collected using this hardware on an alpha-titanium alloy (Ti-7Al) under in situ tensile deformation at the Advanced Photon Source, Argonne National Laboratory. We present both near-field HEDM data that maps out the grain morphology and intragranular crystallographic orientations and far-field HEDM data that provides the grain centroid, grain average crystallographic orientation, and grain average elastic strain tensor for each grain. Finally, we provide a finite element mesh that can be utilized to simulate deformation in the volume of this Ti-7Al specimen. The dataset supporting this article is available in the National Institute of Standards and Technology (NIST) repository (http://hdl.handle.net/11256/599).

Evaluation of grain-average stress tensor in a tensile-deformed Al–Mn polycrystal by high-energy X-ray diffraction

“…The close agreement between the two data sets is remarkable, which makes them amenable for use with crystal plasticity simulations. The volume characterized here is somewhat smaller than the volume used in the comparison of Nervo et al (2014), but larger than the volume characterized with far-field and nearfield high-energy diffraction microscopy (HEDM) (Turner et al, 2016). In the latter case the three-dimensional structure is reconstructed layer by layer, which requires longer acquisition times.…”

“…Such model structures, however, do not capture the true interaction between neighbour grains, which requires simulations on the real three-dimensional geometry. This means that the challenge of a grain-by-grain comparison requires combining farfield (Oddershede et al, 2010) and near-field (Johnson et al, 2008;Li & Suter, 2013) techniques, as recently done by Turner et al (2016). It is one of the aims of the present work to propose such a coupling between diffraction contrast tomography (DCT) (Johnson et al, 2008;Reischig et al, 2013) and 3DXRD.…”

Digital/virtual microstructures in application to metals engineering – A review

“…Obtaining three-dimensional digital representations based on experimental data is more demanding and requires application of advanced experimental procedures, such as X-ray diffraction contrast tomography or near-field highenergy X-ray diffraction microscopy (nf-HEDM) [31]. Techniques based on high energy X-ray diffraction can provide large set of 3D information on morphological features of investigated metallic microstructures and they are also classified as nondestructive approaches.…”

“…Techniques based on high energy X-ray diffraction can provide large set of 3D information on morphological features of investigated metallic microstructures and they are also classified as nondestructive approaches. In the case, a microstructure can be investigated prior and after deformation or even under in situ conditions [31]. However, these methods in application to metals are still expensive and not easily accessible.…”

Instantiation of crystal plasticity simulations for micromechanical modelling with direct input from microstructural data collected at light sources

“…However, despite the specific use here of FFT-based models, the proposed methodology is general, i.e. easily extendable and applicable to instantiate other popular full-field models, like CP Finite Elements (CPFE), from HEDM experimental data [15,16].…”