PhD Thesis Presentation: Commissioning a Novel Quad Near Field Detector for High Energy X-Ray Diffraction Microscopy with Preliminary Applications to an Aluminum Alloy

PhD Candidate

Scott Annett

Abstract

The focus of this work is the commissioning of the Quad Near Field Detector (QNFD) for High Energy Diffraction Microscopy (HEDM) and show its usefulness for material science. A promising feature of such detectors is that they enable non-destructive, in-situ studies of material systems. This design has four times the active area of comparable detectors, allowing for longer working distances or the collection of greater scattering angles. The QNFD was characterized at the Advanced Photon Source using a gold calibrant. All four quadrants of the QNFD were refined independently, with detector translation errors ≤ ±1 μm vertically and ≤ ±3 μm horizontally. An investigation into the microstructure of a novel aluminum alloy designed for high thermal and electrical conductivity was also completed. With diffraction projections collected by the QNFD, a reconstruction of the alloys primary phase aluminum grains was attained. Evidence of a network of intermetallic phases can be seen in these reconstructions. A high contrast filter applied during post processing to highlight this network. The reconstructions display primary phase grain and secondary dendritic arm behavior. Future improvements and potential experiments for the QNFD are discussed.

Examination Committee

• Dr. Eric Poisson, Chair
• Dr. Stefan Kycia, Advisor
• Dr. Ralf Gellert
• Dr. De-Tong Jiang
• Dr. Jonathan Lang, External Examiner (Argonne National Laboratory)