Deconvolution of Superposed Pole Figures by Discrete ODF Methods:Comparison of ADC and WIMV for Quartz and Calcite With TrigonalCrystal and Triclinic Specimen Symmetry

Abstract

Discrete methods of orientation distribution (ODF) analysis are applied to quartz and calcite rocks with trigonol crystal and triclinic sample symmetry. ODF’s are calculated from pole figures measured by neutron diffraction. A particular complication for quartz is the presence of overlapping peaks which can be separated with the WIMV or ADC algorithms based on diffraction intensity differences. Both methods provide similar solutions. Characteristic differences are discussed. By comparing ODF’s obtained from different data subsets (changing number and extent of pole figures) it is concluded that quantity and quality of data, as well as the texture type, have a crucial influence on resolution. It is demonstrated that discrete methods provide the possibility to obtain quantitative texture information from minimal experimental data.

Reliability criteria in quantitative texture analysis with experimental and simulated orientation distributions

“…Many different formalisms may be used for ODF refinements, each of them presenting its own advantages (Wenk et al, 1994). In this study, the WIMV approach has been utilized, mainly because all the data were allowable after about ten years of intensive use of this formalism.…”

In situ deformation apparatus for time-of-flight neutron diffraction:Texture development of polycrystalline ice Ih

“…We used the extended-Williams-Imhof-Matthies-Vinel ͑E-WIMV͒ algorithm direct method to compute our spectra collected on HIPPO. 13 We used the program to calculate the pole figures for the relevant ice diffraction peaks. Texture analyses of these two time intervals reveal a similar pole distribution for the sample as time increases, with twice as many ͑0002͒ poles parallel to the compression axis than as normal to it.…”

Residual stresses of a magnesium alloy (AZ31) welded by the friction stir welding processes

“…The values used in the calculation of residual stress were as follows: S 1 (-5, 58 10 -6 MPa -1 ) and S 2 (26.04. 10 -6 MPa -1 ) [13,14,15]. In the case of textured zones, the residual stresses were calculated taking into account the anisotropic polycrystalline constants.…”

“…In this case the radio-crystallographic elastic constants hkl F I\ (equation 2) were determined from the ODF. In both cases a homogeneous Kröner-Eshelby self-consistent model was used [14,15]. With the X-ray measurement technique used only the superficial layer of the metal (several microns) interact with the X-ray beam.…”