Projects per year
First, we use the intensity ratios of split diffraction peaks to extract grain-scale domain volume fractions for 139 grains. We find that even in the as-processed state there exist unequal volume fractions of each domain type, which we attribute to a heterogeneous local environment at the cubic to tetragonal transition during processing. When a field is applied, we observe a first-order orientation dependence with second order deviations, again attributed to the grain neighbourhood effect. Corellation of this with microstructural parameters such as grain size, neighbour misorientation and position within the sample did not reveal any obvious causes.
Next we develop a novel indexing and refinement method whereby the peak positions of domains are forward projected from crystallographic twinning orienations and the deviation between projected and measured diffraction patterns is minimized to refine domain-scale orientations and lattice parameters. We present the results of refinement for a bulk grain in which the domains are found to be misoriented from perfect crystallographic twins by 0.1-0.3°, suggesting a strained microstructure. The data set was collected by illuminating the entire width of the sample with a box beam, thus it contains a statistically significant number of grains for which domain-scale parameters will be refined in the future.
|Publisher||Department of Physics, Technical University of Denmark|
|Number of pages||159|
|Publication status||Published - 2016|
Majkut, M., Oddershede, J., Poulsen, H. F., Clausen, B., Grant Webber, K. & Schmidt, S.
15/03/2013 → 22/06/2016
Oddershede, J., Schmidt, S. & Majkut, M.
01/01/2013 → 14/03/2016