
Residual and intrinsic strains in granular materials have been studied extensively. However, understanding the dynamic strains that cause these resultant residual strains is key to developing better strain-resistant materials. This investigation demonstrates a method for characterizing dynamic strain propagation in granular materials. The specimen is a zirconia-based refractory composed of sol–gel-derived zirconia nanoparticles in a potassium silicate glass binder. In situ synchrotron X-ray powder diffraction in flat-plate geometry is used to characterize the sample structure on timescales of the order of 1 ms. A 125 W CO2 laser is used to strain the sample with a 25 ms pulse length. To compensate for the poor flux on this timescale, a pump–probe method is repeated 1000 times and the resulting data are subsequently re-binned to improve statistics. A Gaussian weighting function is also used to introduce better contrast between strained and unstrained frames. TOPAS Academic is used for fitting with a Le Bail model in `batch mode'. Lattice parameters and sample height are refined during fitting, along with a Lorentzian line width for extracting microstrain broadening. Microstrains,
, in the range of 1.01 <
< 1.46% are reported on a 1 ms timescale.
![[epsilon]](/logos/entities/epsiv_rmgif.gif)
![[epsilon]](/logos/entities/epsiv_rmgif.gif)
Keywords: lasers; in situ X-ray powder diffraction; zirconia; dynamic strain; microstrain; structural refinement; whole powder pattern fitting.
Supporting information
![]() | Portable Document Format (PDF) file https://doi.org/10.1107/S1600576715002393/kc5003sup1.pdf |