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The spatial organization and interactions of constituent components influence cell growth and determine physical and chemical properties of the cell wall, including its rigidity, flexibility, and degradability. Elucidating the interactions between cell wall polysaccharides is crucial for advancing our knowledge of how cell walls are assembled and for designing approaches to efficiently break down cell walls to produce renewable energy and biomaterials. Here, we investigated the effect of defects in the biosynthesis of cell wall components on the nanoscale organization of cellulose in primary cell walls through grazing incidence wide angle X-ray scattering (GIWAXS) measurements of hypocotyls of wild type Arabidopsis thaliana and of cellulose, pectin, and xyloglucan (hemicellulose) deficient mutants. GIWAXS reveals changes in lattice spacings, coherence lengths, and relative crystalline content for cellulose between wild type and mutant plants. In addition, X-ray pole figures constructed using GIWAXS and X-ray diffraction (XRD) rocking scans quantify an emerging measure of cellulose organization, the degree of preferred orientation (texture) of cellulose crystals with respect to the cell wall plane. Comparing X-ray pole figures from pectin-deficient and xyloglucan-deficient mutants to that of wild type plants reveals that cellulose texture is disrupted in pectin-deficient mutants, but not in xyloglucan mutants. Our results indicate that a deficiency of pectin during cell wall biosynthesis alters cellulose organization in plant cell walls.

The crystallographic texture formation in the AK9ch aluminum alloy (9.6% Si; 0.3% Mg; 0.1% Fe; 0.1% Mn, Al balance) specimens manufactured using the Additive Friction Stir Deposition (AFS-D) technology at room temperature is investigated. The analysis was conducted using inverse pole figures (IPFs) obtained by X‑ray diffraction methods. The results reveal the presence of shear, torsion, deformation, and recrystallization texture components in both types of specimens. The texture of horizontal and vertical samples differs in the set of texture components and the character of their dispersion. The texture intensity of both types of specimens is ill-defined. This testifies to the possibility of manufacturing the AK9ch alloy components using AFS‑D technology with reduced anisotropy.

Compositional and anatomical studies of silicified wood have been carried out extensively all around the world. The classification of silicified wood as such deals with all the forms and phases of silica that come under its umbrella. One such class of silicified wood is fossil wood with a high content of quartz, and there are very limited mentions of this category of fossilized wood. The examined wood belongs to gymnosperm and comes from the Upper Triassic deposits of Madagascar. A fresh approach to such samples is adopted by studying the crystallographic texture of the fossil wood to understand the orientation of the crystals replacing the organic matter within the sample. This work focuses on crystallographic texture analysis based on pole figures measured by X-ray diffraction. The intensity of the pole density maxima on the pole figures measured on the heartwood surface part of the analyzed samples is higher than that on the sapwood. This affirms that the crystallographic texture is sharper at the heartwood part compared to the sapwood. The X-ray tomography study, conducted to understand the difference in mineral distribution within the sample, reveals a greater X-ray absorbing phase on the sapwood of both samples. This is due to the concentration of iron compounds, which both replace the remaining conductive structures of the wood and fill the cavities inside them. We believe that this research on silicified wood is the first research work that encompasses crystallographic texture analysis with pole figures, an approach not previously undertaken in similar studies. We hope that our research can be useful in understanding the processes of replacement of organic matter by minerals.

The volume fraction of austenite (γ), ε martensite and α′ martensite is of key importance in the research of TWIP/TRIP steels. When mechanical loading is involved, the crystallographic texture also develops, which complicates X-ray diffraction-based phase ratio determination. The problem is more pronounced when only a couple, or only one Bragg-reflection can be measured. A solution for such cases is to determine the ratio of the phases based on the pole distribution function of a selected Bragg-reflection of the present phases. In this manuscript, this method is reconsidered for and applied to non-transmittable bulk specimens for the first time in the reflection mode of XRD pole figure measurements. First, the method was applied to a series of γ–α′ powder mixtures. The results were compared to those obtained by the Rietveld method. Afterwards, the technique was applied to strongly textured, bulk TWIP/TRIP steel specimens which were tensile tested at different temperatures. It was shown that the results of the presented method were close to those of the Rietveld technique in the case of powder mixtures. The results of the tensile-tested steels revealed that the α′ content increases with decreasing test temperatures, and the variation of the α′ ratio correlates very well with the ultimate tensile strength versus the temperature, confirming the contribution of the α′ content to the strength of TWIP/TRIP steels.

The ICME paradigm has helped to shift the materials field to be more quantitative, but some topical areas, such as texture comparisons, have lagged behind due to the scarcity of numeric datasets. Texture data is usually published only as visualizations like pole figures, which inhibits its reusability. DRAGON is a newly developed, MATLAB-based tool for extracting quantitative data from pole figures and reconstructing an orientation distribution function (ODF), by interpolating between datapoints placed by the user along contour lines and at local extrema. This work introduces the workflow and user interface of DRAGON and then investigates the uncertainty due to human–computer interaction during use of the tool. The reconstruction process is most robust against user-based error for highly symmetric systems and is most sensitive to variance in placement of local extrema of the pole figures. Based on this analysis, specific recommendations are made for reducing user-based error.

In this paper, the pole figures plotted from X-ray diffraction data are employed to analyze the orientation of hydroxyapatite in ivory and mammoth ivory for the first time. The results present evidence of the lamellar structure and the hydroxyapatite appeared as tabular. A preferred orientation of hydroxyapatite was revealed in terms of the calculated orientation factor and the characteristics found in the pole figures. The c-axes of hydroxyapatite are mainly oriented along the growth direction. Both a-axes are on the left of the angle bisector of Retzius. Approximately 25–30° separates the a-axes and the angle bisector of Retzius in ivory, whereas the figure is approximately 10–15° in mammoth ivory. Our work is significant in providing more accurate knowledge of the shapes and organizational state of bio-mineral crystals and providing insight into crystal formation and development in bio-mineralization.

A comparative study of the orientation distribution functions (ODFs) calculated from direct pole figures (DPFs) is carried out using a superposition of a large number of positive standard Gaussian normal distributions with the same scattering (Texxor software) and the method of arbitrarily defined cells (ADC) (LaboTex software) in order to identify the advantages and shortcomings of each method. The comparison is performed for the Santa Fe reference orientation (the previously calculated total DPFs were used as the experimental DPFs) and the measured incomplete DPFs characterizing the recrystallization textures of 6016 aluminum alloy with a high degree of sharpness. The RP factor is used as a criterion for evaluating the calculation errors for both programs: the difference between the intensities of the experimental and calculated DPFs averaged over each and all measured DPFs and assigned to the corresponding experimental values on the pole figure. The values of the RP factors depend on the method of the ODF reconstruction and the experimental errors of the measured pole figures of the materials under study. It is shown that the values of the RP (0.5) factor (normalized intensities used in the calculation, ≥0.5) for Santa Fe are 0.3 (Texxor) and 2.6% (LaboTex). The corresponding maximum values of the orientation density of ODF differ insignificantly (5.1 and 4.5, respectively). However, for measured incomplete DPFs of the recrystallization texture of aluminum alloy, they differ substantially (61.8 and 95.9), and the RP (0.5) factor increases to 12.6 and 30.5%, respectively. Since the method of superposition of normal distributions provides a lower value of the RP (0.5) factor compared to the ADC method, the ODF recovery using the Texxor software is preferable compared to that with LaboTex.

CVD-coated cemented carbides are widely used for various metal cutting applications. It has been established that the textures of the coating materials especially that of the α-Al2O3 greatly affect the cut performance for some applications. The characterization of the coating texture is thus very important. In this paper, inverse pole figures of α-Al2O3 based on XRD with Bragg Brentano geometry were calculated for several metal cutting inserts available in the market. This method is simple, less time-consuming and can be applied to previously collected data and is compared with that of the EBSD. Despite several differences, IPF maps based on XRD powder diffraction represent the texture of metal cutting inserts.

Comprehensive information on in situ microstructural and crystallographic changes during the preparation/manufacturing processes of various materials is highly necessary to precisely control the microstructural morphology and the preferred orientation (or texture) characteristics for achieving an excellent strength–ductility–toughness balance in advanced engineering materials. In this study, in situ isothermal annealing experiments with cold-rolled 17Ni-0.2C (mass%) martensitic steel sheets were carried out by using the TAKUMI and ENGIN-X time-of-flight neutron diffractometers. The inverse pole figures based on full-profile refinement were extracted to roughly evaluate the preferred orientation features along three principal sample directions of the investigated steel sheets, using the General Structure Analysis System (GSAS) software with built-in generalized spherical harmonic functions. The consistent rolling direction (RD) inverse pole figures from TAKUMI and ENGIN-X confirmed that the time-of-flight neutron diffraction has high repeatability and statistical reliability, revealing that the principal preferred orientation evaluation of steel materials can be realized through 90° TD ➜ ND (transverse direction ➜ normal direction) rotation of the investigated specimen on the sample stage during two neutron diffraction experiments. Moreover, these RD, TD, and ND inverse pole figures before and after the in situ experiments were compared with the corresponding inverse pole figures recalculated from the MUSASI-L complete pole figure measurement and the HIPPO in situ microstructure evaluation, respectively. The similar orientation distribution characteristics suggested that the principal preferred orientation evaluation method can be applied to the in situ microstructural evolution of bulk orthorhombic materials and spatially resolved principal preferred orientation mappings of large engineering structure parts.

A theoretical and experimental study was carry out to investigate deformation mechanisms in a textured titanium alloy. In situ neutron diffraction measurements were performed to analyze different {hk.l} family planes ({10.0}, {10.1}, {11.0} and {00.2}) and determine the corresponding internal strain pole figures. This method was applied to a pure titanium (a-Ti) submitted to a uniaxial tensile load up to 2 %. The experimental data was then used to validate the EPSC model in order to predict the distribution of lattice strains determined by neutron diffraction for various diffraction vector directions. This comparison reveals that the model results were in good agreement with the experimental data and the simulations reproduced the lattice strain development observed on the strain pole figures determined by neutron diffraction.