Analysis of Polycrystalline Microstructure of AlMgSc Alloy Observed by 3D EBSD

Jaromír Kopeček; Jakub Staněk; Stanislav Habr; Filip Seitl; Lukas Petrich; Volker Schmidt; Viktor Beneš

doi:10.5566/ias.2224

Authors

Jaromír Kopeček Institute of Physics of the CAS, Department of Functional Materials, Na Slovance 2, 182 00 Prague 8
Jakub Staněk Department of Mathematics Education, Faculty of Mathematics and Physics, Charles University, 18675 Prague
Stanislav Habr Institute of Physics of the CAS, Department of Functional Materials, Na Slovance 2, 182 00 Prague 8
Filip Seitl Department of Probability and Mathematical Statistics, Faculty of Mathematics and Physics, Charles University, 18675 Prague
Lukas Petrich Institute of Stochastics, Faculty of Mathematics and Economics, Ulm University, 89069 Ulm
Volker Schmidt Institute of Stochastics, Faculty of Mathematics and Economics, Ulm University, 89069 Ulm
Viktor Beneš Department of Probability and Mathematical Statistics, Faculty of Mathematics and Physics, Charles University, 18675 Prague

DOI:

https://doi.org/10.5566/ias.2224

Keywords:

3D EBSD, grain boundaries, misorientation, polycrystalline microstructure, statistical image analysis

Abstract

The aim of this paper is to evaluate an ambitious imaging experiment and to contribute to the methodology of statistical inference of the three-dimensional microstructure of polycrystalline materials. The microstructure of the considered Al-3Mg-0.2Sc alloy was investigated by three-dimensional electron backscattered diffraction (3D-EBSD), i.e., tomographic imaging with xenon plasma focused ion beam (Xe-FIB) alongside EBSD. The samples were subjected to severe plastic deformations by equal channel angular pressing (ECAP) and annealed subsequently prior to the mapping. First we compared the misorientation level needed for a reliable segmentation of grains distinguishing between conventional evaluation of two-dimensional cuts and the 3D data set. Then, using methods of descriptive spatial statistics, various morphological characteristics of a large number of grains were analyzed, as well as the crystallographic texture and the spatial distribution of grain boundaries. According to the results stated so far in the literature, an even microstructure was expected, nevertheless local inhomogeneities in grains and grain boundaries with regard to their size, texture and spatial distribution were observed and justified.

References

Burnett TL, Kelley R, Winiarski B, Contreras L, DalyM, Gholinia A, Burke MG, Wither PJ (2016).Large volume serial section tomography by Xe-Plasma FIB dual beam microscopy. Ultramicrosc161:119-29.

Chiu SN, Stoyan D, Kendall WS, Mecke J (2013).Stochastic Geometry and Its Applications, 3rdedition. Chichester: John Wiley & Sons.

Dám K, Lejček P, Michalcová A (2013). In situTEM investigation of microstructural behavior ofsuperplastic Al–Mg–Sc alloy. Mat Char 76:69-75.

Donegan SP, Tucker JC, Rollett AD, Barmak K,Groeber M (2013). Extreme value analysis oftail departure from log-normality in experimentaland simulated grain size distributions. Acta Mater,61(15):5595-604.

Engler O, Randle V (2010). Introduction to TextureAnalysisMacrotexture,Microtexture,andOrientation Mapping, 2nd Edition. Boca Raton:CRC Press.

Groeber MA, Jackson MA (2014). DREAM.3D: Adigital representation environment for the analysisof microstructure in 3D. Integ Mat Manuf Innov3:5-17.

Horita Z, Furukawa M, Nemoto M, Barnes AJ,Landgon TG (2000). Superplastic forming at highstrain rates after severe plastic deformation. ActaMat 48(14):3633-40.

Kawasaki M, Horita Z, Langdon TG (2009).Microstructural evolution in high purity aluminumprocessed by ECAP. Mat Sci Eng A 524:143-50

Lee S, Utsunomiya A, Akamatsu H, Neishi K,Fukurawa M, Horita Z, Langdon TG (2002).Influence of scandium and zirconium on grainstability and superplastic ductilities in ultrafine-grained Al–Mg alloys. Acta Mat 50(3):553-64.

Mackenzie JK (1958). Second paper on statisticsassociated with the random disorientation of cubes.Biometrika 45:229-240.

Mingard KP, Steward M, Gee MG, Vespucci S, Trager-Cowan C (2018). Practical application of directelectron detectors to EBSD mapping in 2D and 3D.Ultramicrosc 184:184-242.

Nishikawa S, Kikuchi S (1928). Diffraction of cathoderays by calcite. Nature 122:726-726.

Schwartz AJ, Kumar M, Adams BL, Field DP (2009).Electron Backscatter Diffraction in MaterialsScience, 2nd Edition. Boston: Springer.

Skrytnyy VI, Gavrilov MV,Khramtsova TP,Kolyanova AS, Krasnov A, Porechniy SV, YaltsevVN, (2017). Misorientation distributionfunction of crystals. In: 15th International School-Conference on new materials of innovativeenergy: development, characterization methodsand application, KnE Materials Science, 342-357.

Šedivý O, Beneš V, Ponížil P, Král P, Sklenička V(2013).Quantitativecharacterizationofmicrostructure of pure copper precessed by ECAP.Image Anal Stereol 32:65-75.

Valiev RZ, Langdon TG (2006). Principles of equal-channel angular pressing as a processing tool forgrain refinement. Prog Mater Sci 51(7):881-981.

Xu Ch, Horita Z, Langdon TG (2011). Microstructuralevolution in an aluminum solid solution alloyprocessed by ECAP. Mat Sci Eng A, 528:6059-65.

Zaefferer S (2005). Application of orientationmicroscopy in SEM and TEM for the studyof texture formation during recrystallisationprocesses. Textures of matherials - ICOTOM 14.Mat Sci Forum 495-497:3-12