Practice for Determining Average Grain Size Using Electron Backscatter Diffraction (EBSD) in Fully Recrystallized Polycrystalline Materials

AbstractA Cobalt-20wt.% Nickel polycrystal produced by electrodeposition has been investigated in planar and cross sections using a high resolution scanning electron microscope. The local texture, grain size, amount of phase and grain boundaries, were characterized by Electron Backscatter Diffraction (EBSD). The average grain size perpendicular to the grain growth direction was 400 nm. Parallel to it, a pronounced bimodal grain structure was observed with grains reaching more than 10 μm and grains of approximately 800 nm diameter.

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Application of Electron Backscatter Diffraction (EBSD) for Crystallographic Characterization of Aluminum-Doped Zinc Oxide Sputtered Films

Microscopy and Microanalysis ◽

10.1017/s143192761300113x ◽

2013 ◽

Vol 19 (S4) ◽

pp. 103-104

Author(s):

C.B. Garcia ◽

E. Ariza ◽

C.J. Tavares

Keyword(s):

Electron Microscopy ◽

Grain Size ◽

Zinc Oxide ◽

Electron Backscatter Diffraction ◽

Wide Range ◽

Electron Backscatter ◽

Aluminum Doped Zinc Oxide ◽

Ebsd Technique ◽

Backscatter Diffraction

Zinc Oxide is a wide band-gap compound semiconductor that has been used in optoelectronic and photovoltaic applications due to its good electrical and optical properties. Aluminium has been an efficient n-type dopant for ZnO to produce low resistivity films and high transparency to visible light. In addition, the improvement of these properties also depends on the morphology, crystalline structure and deposition parameters. In this work, ZnO:Al films were produced by d.c. pulsed magnetron sputtering deposition from a ZnO ceramic target (2.0 wt% Al2O3) on glass substrates, at a temperature of 250 ºC.The crystallographic orientation of aluminum doped zinc oxide (ZnO:Al) thin films has been studied by Electron Backscatter Diffraction (EBSD) technique. EBSD coupled with Scanning Electron Microscopy (SEM) is a powerful tool for the microstructural and crystallographic characterization of a wide range of materials.The investigation by EBSD technique of such films presents some challenges since this analysis requires a flat and smooth surface. This is a necessary condition to avoid any shadow effects during the experiments performed with high tilting conditions (70º). This is also essential to ensure a good control of the three dimensional projection of the crystalline axes on the geometrical references related to the sample.Crystalline texture is described by the inverse pole figure (IPF) maps (Figure 1). Through EBSD analysis it was observed that the external surface of the film presents a strong texture on the basal plane orientation (grains highlighted in red colour). Furthermore it was possible to verify that the grain size strongly depends on the deposition time (Figure 1 (a) and (b)). The electrical and optical film properties improve with increasing of the grain size, which can be mainly, attributed to the decrease in scattering grain boundaries which leads to an increasing in carrier mobility (Figure 2).The authors kindly acknowledge the financial support from the Portuguese Foundation for Science and Technology (FCT) scientific program for the National Network of Electron Microscopy (RNME) EDE/1511/RME/2005.

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Diffracting-grain identification from electron backscatter diffraction maps during residual stress measurements: a comparison between the sin2ψ and cosα methods

Journal of Applied Crystallography ◽

10.1107/s1600576719008744 ◽

2019 ◽

Vol 52 (4) ◽

pp. 828-843 ◽

Cited By ~ 1

Author(s):

Dorian Delbergue ◽

Damien Texier ◽

Martin Lévesque ◽

Philippe Bocher

Keyword(s):

Residual Stress ◽

Grain Size ◽

Tilt Angle ◽

Measurement Errors ◽

Electron Backscatter Diffraction ◽

Measurement Techniques ◽

Single Exposure ◽

X Ray ◽

Electron Backscatter ◽

Backscatter Diffraction

X-ray diffraction (XRD) is a widely used technique to evaluate residual stresses in crystalline materials. Several XRD measurement methods are available. (i) The sin2ψ method, a multiple-exposure technique, uses linear detectors to capture intercepts of the Debye–Scherrer rings, losing the major portion of the diffracting signal. (ii) The cosα method, thanks to the development of compact 2D detectors allowing the entire Debye–Scherrer ring to be captured in a single exposure, is an alternative method for residual stress measurement. The present article compares the two calculation methods in a new manner, by looking at the possible measurement errors related to each method. To this end, sets of grains in diffraction condition were first identified from electron backscatter diffraction (EBSD) mapping of Inconel 718 samples for each XRD calculation method and its associated detector, as each method provides different sets owing to the detector geometry or to the method specificities (such as tilt-angle number or Debye–Scherrer ring division). The X-ray elastic constant (XEC) ½S 2, calculated from EBSD maps for the {311} lattice planes, was determined and compared for the different sets of diffracting grains. It was observed that the 2D detector captures 1.5 times more grains in a single exposure (one tilt angle) than the linear detectors for nine tilt angles. Different XEC mean values were found for the sets of grains from the two XRD techniques/detectors. Grain-size effects were simulated, as well as detector oscillations to overcome them. A bimodal grain-size distribution effect and `artificial' textures introduced by XRD measurement techniques are also discussed.

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Effect of Annealing Time on the Microstructure and Texture of Interstitial Free Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.535-537.593 ◽

2012 ◽

Vol 535-537 ◽

pp. 593-596

Author(s):

Zhi Fen Wang ◽

Rong Dong Han ◽

Shun Bing Zhou ◽

Zhong Hai Yao ◽

Li Xin Wu

Keyword(s):

Grain Size ◽

Annealing Time ◽

Electron Backscatter Diffraction ◽

Recrystallization Process ◽

Interstitial Free ◽

X Ray Diffraction ◽

Steel Sheets ◽

Grain Boundary Character ◽

Average Grain Size ◽

Backscatter Diffraction

Effect of annealing time on the microstructure and texture of IF steel sheets was investigated. Average grain size, grain boundary character and recrystallization texture were measured by X-ray diffraction (XRD) and electron backscatter diffraction (EBSD) in order to clarify the effect of annealing time on microstructure of recrystallization process. The average grain size increased with increasing annealing time. With rising annealing time, the number of low angle boundary (0～15o) decreased due to the mergence of grain with sub-boundary. The //ND (-fiber) pole intensity had a highest value annealed at 60s. The annealing time played an important role in recrystallization process which affected the mechanical properties and microstructure of IF steels.

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