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X-ray micro Laue diffraction tomography analysis of a solid oxide fuel cell.

Ferreira Sanchez D, Villanova J, Laurencin J, Micha JS, Montani A, Gergaud P, Bleuet P - J Appl Crystallogr (2015)

Bottom Line: For this purpose, a multiphase solid oxide fuel cell (SOFC) electrode composite made of yttria-stabilized zirconia and nickel oxide phases, with grains of about a few micrometres in size, has been analyzed.The SOFC and germanium Laue diffraction pattern analyses are compared and discussed.The development and application of an original geometrical approach to analyze the SOFC Laue data allowed the authors to resolve grains with sizes of about 3 µm and to identify their individual Laue patterns; by indexing those Laue patterns, the crystalline phases and orientations of most of the grains identified through the geometrical approach could be resolved.

View Article: PubMed Central - HTML - PubMed

Affiliation: Université Grenoble Alpes , Grenoble, F-38000, France ; CEA/LETI , MINATEC Campus, Grenoble, F-38054, France.

ABSTRACT

The relevance of micro Laue diffraction tomography (µ-LT) to investigate heterogeneous polycrystalline materials has been studied. For this purpose, a multiphase solid oxide fuel cell (SOFC) electrode composite made of yttria-stabilized zirconia and nickel oxide phases, with grains of about a few micrometres in size, has been analyzed. In order to calibrate the Laue data and to test the technique's sensitivity limits, a monocrystalline germanium sample of about 8 × 4 µm in cross-section size has also been studied through µ-LT. The SOFC and germanium Laue diffraction pattern analyses are compared and discussed. The indexing procedure has been successfully applied for the analysis of the germanium Laue data, and the depth-resolved two-dimensional cartographies of the full deviatoric strain tensor components were obtained. The development and application of an original geometrical approach to analyze the SOFC Laue data allowed the authors to resolve grains with sizes of about 3 µm and to identify their individual Laue patterns; by indexing those Laue patterns, the crystalline phases and orientations of most of the grains identified through the geometrical approach could be resolved.

No MeSH data available.


Related in: MedlinePlus

The inverse pole figures obtained from (a) all the indexed Laue patterns measured for Ge and from (b) all the identified average grain Laue patterns. Again, (c) the origram of the grains identified through the geometrical approach and (d) the respective SIRT. Here is indicated the position of one identified grain from (b), from which (e) the isolated diffracted intensity origram and its ξ were discriminated. With those origrams, (f) the grain position and (g) the two-dimensional map of the qualitative information about the fluctuations of the unit-cell shape and/or crystalline misorientation were obtained.
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fig6: The inverse pole figures obtained from (a) all the indexed Laue patterns measured for Ge and from (b) all the identified average grain Laue patterns. Again, (c) the origram of the grains identified through the geometrical approach and (d) the respective SIRT. Here is indicated the position of one identified grain from (b), from which (e) the isolated diffracted intensity origram and its ξ were discriminated. With those origrams, (f) the grain position and (g) the two-dimensional map of the qualitative information about the fluctuations of the unit-cell shape and/or crystalline misorientation were obtained.

Mentions: The orientations of the NiO grains, as well as of the Ge monocrystal, have been obtained through the indexing procedure. These obtained crystallographic orientations with respect to the tomographic rotation axis are represented in the inverse pole figures shown in Figs. 6 ▶(a) and 6 ▶(b). Each dot in Fig. 6 ▶(a) corresponds to a Ge orientation obtained from a Laue image, and each dot in Fig. 6 ▶(b) corresponds to an NiO grain orientation obtained from an identified average grain Laue pattern. In Fig. 6 ▶(a), the dots form an elliptical-like shape, and in Fig. 6 ▶(b), a collection of truncated ellipses. The elliptical shape observed in Fig. 6 ▶(a) has its origin in a small sample misalignment, which has an angle precession of about 3°. The ellipses in Fig. 6 ▶(b) are truncated, which may be due either to absorption effects or to sample misalignment. For the inverse pole figure construction, the absorption affects most of the grains positioned close to the borders of the sample, when they are on the opposite side with respect to the two-dimensional detector. The misalignment may lead to a change of illuminated volume upon rotation, and it affects mostly grains located far from the rotation axis, which may rotate out of the beam.


X-ray micro Laue diffraction tomography analysis of a solid oxide fuel cell.

Ferreira Sanchez D, Villanova J, Laurencin J, Micha JS, Montani A, Gergaud P, Bleuet P - J Appl Crystallogr (2015)

The inverse pole figures obtained from (a) all the indexed Laue patterns measured for Ge and from (b) all the identified average grain Laue patterns. Again, (c) the origram of the grains identified through the geometrical approach and (d) the respective SIRT. Here is indicated the position of one identified grain from (b), from which (e) the isolated diffracted intensity origram and its ξ were discriminated. With those origrams, (f) the grain position and (g) the two-dimensional map of the qualitative information about the fluctuations of the unit-cell shape and/or crystalline misorientation were obtained.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4379434&req=5

fig6: The inverse pole figures obtained from (a) all the indexed Laue patterns measured for Ge and from (b) all the identified average grain Laue patterns. Again, (c) the origram of the grains identified through the geometrical approach and (d) the respective SIRT. Here is indicated the position of one identified grain from (b), from which (e) the isolated diffracted intensity origram and its ξ were discriminated. With those origrams, (f) the grain position and (g) the two-dimensional map of the qualitative information about the fluctuations of the unit-cell shape and/or crystalline misorientation were obtained.
Mentions: The orientations of the NiO grains, as well as of the Ge monocrystal, have been obtained through the indexing procedure. These obtained crystallographic orientations with respect to the tomographic rotation axis are represented in the inverse pole figures shown in Figs. 6 ▶(a) and 6 ▶(b). Each dot in Fig. 6 ▶(a) corresponds to a Ge orientation obtained from a Laue image, and each dot in Fig. 6 ▶(b) corresponds to an NiO grain orientation obtained from an identified average grain Laue pattern. In Fig. 6 ▶(a), the dots form an elliptical-like shape, and in Fig. 6 ▶(b), a collection of truncated ellipses. The elliptical shape observed in Fig. 6 ▶(a) has its origin in a small sample misalignment, which has an angle precession of about 3°. The ellipses in Fig. 6 ▶(b) are truncated, which may be due either to absorption effects or to sample misalignment. For the inverse pole figure construction, the absorption affects most of the grains positioned close to the borders of the sample, when they are on the opposite side with respect to the two-dimensional detector. The misalignment may lead to a change of illuminated volume upon rotation, and it affects mostly grains located far from the rotation axis, which may rotate out of the beam.

Bottom Line: For this purpose, a multiphase solid oxide fuel cell (SOFC) electrode composite made of yttria-stabilized zirconia and nickel oxide phases, with grains of about a few micrometres in size, has been analyzed.The SOFC and germanium Laue diffraction pattern analyses are compared and discussed.The development and application of an original geometrical approach to analyze the SOFC Laue data allowed the authors to resolve grains with sizes of about 3 µm and to identify their individual Laue patterns; by indexing those Laue patterns, the crystalline phases and orientations of most of the grains identified through the geometrical approach could be resolved.

View Article: PubMed Central - HTML - PubMed

Affiliation: Université Grenoble Alpes , Grenoble, F-38000, France ; CEA/LETI , MINATEC Campus, Grenoble, F-38054, France.

ABSTRACT

The relevance of micro Laue diffraction tomography (µ-LT) to investigate heterogeneous polycrystalline materials has been studied. For this purpose, a multiphase solid oxide fuel cell (SOFC) electrode composite made of yttria-stabilized zirconia and nickel oxide phases, with grains of about a few micrometres in size, has been analyzed. In order to calibrate the Laue data and to test the technique's sensitivity limits, a monocrystalline germanium sample of about 8 × 4 µm in cross-section size has also been studied through µ-LT. The SOFC and germanium Laue diffraction pattern analyses are compared and discussed. The indexing procedure has been successfully applied for the analysis of the germanium Laue data, and the depth-resolved two-dimensional cartographies of the full deviatoric strain tensor components were obtained. The development and application of an original geometrical approach to analyze the SOFC Laue data allowed the authors to resolve grains with sizes of about 3 µm and to identify their individual Laue patterns; by indexing those Laue patterns, the crystalline phases and orientations of most of the grains identified through the geometrical approach could be resolved.

No MeSH data available.


Related in: MedlinePlus