We are conducting deformation experiments on Quartz using the D-DIA apparatus. Below are lattice spacings for the quartz (100), (101), and (112) reflections as a function of time during the deformation experiment. The calculated “hydrostatic” d-spacing is shown as a dashed line. The position of each reflection is measured as a function of time during the deformation experiment. D-spacings for the vertical pair of detectors (1 & 2) shrink more than for the horizontal pair (3 & 4), reflecting increasing differential stress.
We use Elastic-Plastic Self-Consistent (EPSC) Models to interpret our diffraction data. EPSC Models assume that ductile deformation is controlled by the motion of dislocations and/or by twinning. We were able to simulate our diffraction data collected at 800°C with an EPSC Model that used only basal and prismatic slip. This is consistent with the slip systems that are thought to operate at this temperature.
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Figure 1. Schematics of slip systems operating in a hexagonal quartz crystal. We use these slip systems in our EPSC models to model the X-ray synchrotron diffraction data.
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Figure 2. Lattice spacings for the quartz (112) (101) and (100) reflections.
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Figure 3. Comparison of macroscopic stress supported by quartz sample as a function of macroscopic strain.