High pressure deformation study of zirconium

Abstract

In situ deformation studies of polycrystalline materials using diffraction are an established method to understand elastic and plastic deformation of materials. Studies of active deformation mechanisms, the interplay of deformation with texture, and ultimately the development of predictive capabilities for deformation modeling are an active field of research. Parameters studied by diffraction are typically lattice strains and texture evolution, which coupled with the macroscopic flow curve allow for improved understanding of the micro-mechanics of deformation. We performed a study of the uniaxial deformation of Zircaloy-2 at 2 GPa at the 13-BM-D beamline at the Advanced Photon Source. The deformation-DIA apparatus generates a confining hydrostatic pressure using a cubic anvil setup. Two differential rams allow an increase (compressive load) or decrease (tensile load) of the uniaxial straining in the vertical direction, allowing studies of plastic deformation at high pressures. In this paper, we describe how macroscopic strains, hydrostatic pressure, and uniaxial strains are derived and present some brief results.

Simulations of in situ x-ray diffraction from uniaxially compressed highly textured polycrystalline targets

“…For example, bulk rotations of the crystal lattice, or changes in the crystal structure, such as Martensitic phase changes, will result in an altered texture that could be used to distinguish between different mechanisms of atomic rearrangement. This reorientation has been observed in previous work using both neutron sources 40 and synchrotrons 35,39 , although only at relatively modest pressures compared with those we are interested in here.…”

“…Indeed, significant static studies of the texture of polycrystalline samples have been undertaken with synchrotron sources for many years. [33][34][35][36][37][38][39] . Wenk and co-workers provide an overview of the use of synchrotrons in such texture analysis 35 .…”

In situ synthesis and characterization of uranium carbide using high temperature neutron diffraction

“…For data refined with the script software gsaslanguage [33], which allows automated analysis of diffraction data using the GSAS Rietveld package, we employed a moving average over five data sets prior to the refinement process as shown to be effective by [34]. Single peak fits, on the other hand, are calculated from individual, not averaged data sets, that were processed with a five-value wide median filter which smoothed the graph significantly, as proven by Vogel et al [35].…”

High Pressure Phase-Transformation Induced Texture Evolution and Strengthening in Zirconium Metal: Experiment and Modeling

“…The sample columns from X-ray radiographic images are used to measure the changes in the sample length during the deformation 28 . Depending on the intensity contrast between sample and strain marker (Au foils), the sample length changes can be measured within 1 micron resolution.…”