Title: Measurement of Stress using Synchrotron X-rays

We present a technique for high pressure and high temperature deformation experiment on single crystals, using the Deformation-DIA apparatus at the X17B2 beamline of the NSLS. While deformation experiments on polycrystalline samples using D-DIA in conjunction with synchrotrons have been previously reported, this technical paper focuses on single crystal application of the technique. Our single crystals are specifically oriented such that only [1 0 0] slip or [0 0 1] slip in (0 1 0) plane is allowed. Constant applied stress (sigma <300 MPa) and specimen strain rates were monitored using in situ time-resolved X-ray diffraction and radiography imaging, respectively.more » Rheological properties of each activated slip system in the crystals can be revealed using this technique. In this paper, we describe the principle of sample preparation (e.g. [1 1 0]c and [0 1 1]c orientations) to activate specific slip systems (i.e. [1 0 0](0 1 0) and [0 0 1](0 1 0), respectively), stress measurement and procedures of the deformation experiments.« less

No abstract prepared.

A shrink-fit sample is manufactured with a Ti-8Al-1Mo-1V alloy to introduce a multiaxial residual stress field in the disk of the sample. A set of strain and orientation pole figures are measured at various locations across the disk using synchrotron high-energy X-ray diffraction. Two approaches—the traditional sin ²Ψ method and the bi-scale optimization method—are taken to determine the stresses in the disk based on the measured strain and orientation pole figures, to explore the range of solutions that are possible for the stress field within the disk. While the stress components computed using the sin ²Ψ method and the bi-scalemore » optimization method have similar trends, their magnitudes are significantly different. Lastly, it is suspected that the local texture variation in the material is the cause of this discrepancy.« less