Evaluation of Dislocation Density for 1100 Aluminum with Different Grain Size during Tensile Deformation by Using <i>In-Situ</i> X-ray Diffraction Technique

In this study, the tensile deformation behavior of an electron beam melted Ti−6Al−4V alloy was examined by in situ X-ray diffraction (XRD) line-profile analysis. The as-built Ti−6Al−4V alloy specimen showed a fine acicular microstructure that was produced through the decomposition of the α′-martensite during the post-melt exposure to high temperatures. Using high-energy synchrotron radiation, XRD line-profile analysis was successfully applied for examining the evolution of dislocation structures not only in the α-matrix but also in the nanosized, low-fraction β-phase precipitates located at the interfaces between the α-laths. The results indicated that the dislocation density was initially higher in the β-phase and an increased dislocation density with increasing applied tensile strain was quantitatively captured in each constitutive phase. It can be thus concluded that the EBM Ti−6Al−4V alloy undergoes a cooperative plastic deformation between the constituent phases in the duplex microstructure. These results also suggested that XRD line-profile analysis combined with highenergy synchrotron XRD measurements can be utilized as a powerful tool for characterizing duplex microstructures in titanium alloys.

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Modeling of strain distribution in non-hydrostatically pressed nanocrystalline sic; in-situ x-ray diffraction study

MRS Proceedings ◽

10.1557/proc-501-305 ◽

1997 ◽

Vol 501 ◽

Cited By ~ 4

Author(s):

R. Pielaszek ◽

S. Stel'Makh ◽

M. Aloshina ◽

S. Gierlotka ◽

B. Palosz

Keyword(s):

Grain Size ◽

Ab Initio ◽

Strain Distribution ◽

Distribution Functions ◽

Scattered Intensity ◽

X Ray Diffraction ◽

X Ray ◽

Diffraction Patterns ◽

Different Grain Size

ABSTRACTGrain size and strain distribution functions of polycrystals of SiC with nanosize grains were examined based on X-ray diffraction data and ab initio calculations of scattered intensity from Debye functions. A tentative model of distribution of strain induced under high isostatic pressure in nanoparticles with different grain size is presented. Nanocrystalline SiC powders with grains down to 80Å in diameter were examined. In situ high pressure diffraction experiments were performed in cubic anvil cell MAX80 (up to 6 GPa) and in Diamond Anvil Cell (DAC) (up to 45 GPa) at HASYLAB, Hamburg, Germany. Shape of the Bragg lines was analysed with the use of two methods: (i) calculation of theoretical diffraction patterns based on modeling of one-dimensional disordering and ab initio calculation of scattered intensity starting from Debye functions and, (ii) approximation of the experimental shape of Bragg reflections by a combination of two functions: Gaussian (G) and Lorentzian (L).

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Transient phase fraction and dislocation density estimation from in-situ X-ray diffraction data with a low signal-to-noise ratio using a Bayesian approach to the Rietveld analysis

Materials Characterization ◽

10.1016/j.matchar.2020.110860 ◽

2020 ◽

pp. 110860

Author(s):

Manfred Wiessner ◽

Paul Angerer ◽

Sybrand van der Zwaag ◽

Ernst Gamsjäger

Keyword(s):

Dislocation Density ◽

Density Estimation ◽

Diffraction Data ◽

Signal To Noise Ratio ◽

Rietveld Analysis ◽

Transient Phase ◽

X Ray Diffraction ◽

Signal To Noise ◽

X Ray

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Dislocations, crystallite size, and planar faults in nanocrystalline ceria

Powder Diffraction ◽

10.1154/1.3187210 ◽

2009 ◽

Vol 24 (3) ◽

pp. 228-233 ◽

Cited By ~ 3

Author(s):

S. R. Aghdaee ◽

V. Soleimanian

Keyword(s):

Grain Size ◽

Dislocation Density ◽

Crystallite Size ◽

Cerium Oxide ◽

Diffraction Line ◽

Line Broadening ◽

X Ray Diffraction ◽

X Ray ◽

Nanocrystalline Ceria ◽

Hall Plot

The modified Williamson–Hall and Warren–Averbach methods were used successfully for analyzing experimentally observed anisotropic X-ray diffraction line broadening and for determining reliable values of crystallite size and dislocation density in cerium oxide. The modified Williamson–Hall plot gives 22.3(2) nm for volume-weighted crystallite size, while the modified Warren–Averbach produces 18.0(2) nm for area-weighted grain size. The dislocation density and effective outer cut-off radius of dislocations obtained from the modified Warren–Averbach method are 1.8(3)×1015 m−2 and 15.5(1) nm, respectively.

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In Situ X-ray Diffraction Study of the Tensile Deformation of U-5.8Nb Alloy

Rare Metal Materials and Engineering ◽

10.1016/s1875-5372(15)30073-4 ◽

2015 ◽

Vol 44 (5) ◽

pp. 1094-1098 ◽

Cited By ~ 3

Author(s):

Zhang Yanzhi ◽

Wang Xiaolin ◽

Chen Xianglin ◽

Xiao Dawu

Keyword(s):

Diffraction Study ◽

Tensile Deformation ◽

X Ray Diffraction ◽

X Ray

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In situ characterization of Grade 92 steel during tensile deformation using concurrent high energy X-ray diffraction and small angle X-ray scattering

Journal of Nuclear Materials ◽

10.1016/j.jnucmat.2013.04.063 ◽

2013 ◽

Vol 440 (1-3) ◽

pp. 81-90 ◽

Cited By ~ 28

Author(s):

Leyun Wang ◽

Meimei Li ◽

Jonathan Almer

Keyword(s):

Small Angle ◽

Tensile Deformation ◽

High Energy ◽

X Ray Diffraction ◽

In Situ Characterization ◽

X Ray ◽

X Ray Scattering ◽

Grade 92 Steel

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In-situ X-ray diffraction during tensile deformation of ultrafine-grained copper using synchrotron radiation

Philosophical Magazine Letters ◽

10.1080/09500839.2016.1218563 ◽

2016 ◽

Vol 96 (8) ◽

pp. 294-304 ◽

Cited By ~ 10

Author(s):

Yoji Miyajima ◽

Satoshi Okubo ◽

Tomotaka Miyazawa ◽

Hiroki Adachi ◽

Toshiyuki Fujii

Keyword(s):

Synchrotron Radiation ◽

Tensile Deformation ◽

X Ray Diffraction ◽

X Ray ◽

Ultrafine Grained

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Study of Machining-Induced Microstructure Variations of Nanostructured/Ultrafine-Grained Copper Using XRD

Journal of Engineering Materials and Technology ◽

10.1115/1.4003105 ◽

2011 ◽

Vol 133 (2) ◽

Cited By ~ 6

Author(s):

Yong Huang ◽

Mason Morehead

Keyword(s):

Plastic Deformation ◽

Grain Size ◽

Dislocation Density ◽

Equal Channel Angular Extrusion ◽

Outer Radius ◽

X Ray Diffraction ◽

X Ray ◽

Grain Sizes ◽

Ultrafine Grained ◽

Area And Volume

Various methods for the production of bulk nanostructured (NS)/ultrafine-grained (UFG) materials have been developed, including equal channel angular extrusion (ECAE), a form of severe plastic deformation. Using an ECAE NS/UFG copper bar as an example, this study has investigated machining-induced workpiece microstructure variation using X-ray diffraction. It has been found that (1) under gentle cutting conditions, there was a 10% increase in the median grain size compared with unmachined ECAE NS/UFG copper bars. Increases in the arithmetic-, area-, and volume-weighted grain sizes were found to be 10%, 8%, and 8%, respectively, and (2) an average 27% drop in the dislocation density was observed between the machined and unmachined ECAE copper bars. The dislocation density was shown to have the most reduction (−39%) at the outer radius of the machined ECAE bar where more heat and/or higher pressure were experienced.

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