Rietveld analysis of mechanically activated BaCO3–TiO2 system

BaTiO3 powders were prepared through mechanical activation chemistry and analyzed by Rietveld refinement with X-ray diffraction data. Raw BaCO3 and TiO2 powders were dry milled for 5 and 20 h and then calcinated for 2 and 4 h at 800 °C. The milling process was found to have broken up the BaCO3 and TiO2 crystals into smaller crystals and formed only small amounts (<1.5 wt%) of BaTiO3. Subsequence calcinations for 2 and 4 h at 800 °C successfully produced large amounts (>97.7 wt%) of BaTiO3 crystals. The calcination process also generated microstrains and crystallite-size anisotropy in BaTiO3. An increase in the calcination time from 2 to 4 h increased the BaTiO3 weight percentage and the crystallite-shape anisotropy, but decreased the tetragonal distortion anisotropic microstrains in BaTiO3 crystals.

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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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Evolution of crystallographic phases in the system (Pb1−xCax)TiO3: A Rietveld study

Journal of Materials Research ◽

10.1557/jmr.2003.0052 ◽

2003 ◽

Vol 18 (2) ◽

pp. 407-414 ◽

Cited By ~ 33

Author(s):

Amreesh Chandra ◽

Dhananjai Pandey

Keyword(s):

Powder Diffraction ◽

Diffraction Data ◽

Rietveld Analysis ◽

Oxygen Octahedra ◽

X Ray Diffraction ◽

Ceramic Powders ◽

Space Group ◽

X Ray

X-ray powder diffraction studies on (Pb1−xCax)TiO3 ceramic powders revealed the presence of superlattice reflections due to antiphase and inphase tilts of oxygen octahedra for x ≥ 0.421. Rietveld analysis of the powder x-ray diffraction data confirmed that the structure of (Pb1-xCax)TiO3 is orthorhombic with Pbnm space group and a−a−c+ tilt system for x ≥ 0.421. For compositions with 0 < x ≤ 0.416, the structure was tetragonal, and the tetragonality decreased with increasing Ca2+ content.

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Texture development in Bi2Te3 during hot forging

Journal of Materials Research ◽

10.1557/jmr.1998.0097 ◽

1998 ◽

Vol 13 (3) ◽

pp. 766-773 ◽

Cited By ~ 10

Author(s):

E. J. Gonzalez ◽

J. E. Blendell ◽

J. P. Cline ◽

J. J. Ritter ◽

P. Maruthamuthu ◽

...

Keyword(s):

Diffraction Data ◽

Hot Forging ◽

Rietveld Analysis ◽

Texture Development ◽

X Ray Diffraction ◽

Grain Rotation ◽

X Ray ◽

Texture Model ◽

Primary Mechanism ◽

Loading Axis

The development of crystallographic texture in hot-forged polycrystalline Bi2Te3 samples was studied. Texture was evaluated with the use of the March–Dollase model in conjunction with a Rietveld analysis of x-ray diffraction data. It was determined that during forging a strong (0001) texture develops along the loading axis. The magnitude of the (0001) texture increases systematically with the amount of height reduction during hot-forging. The correlation between the observed deformation and the March–Dollase texture model suggests that grain rotation is the primary mechanism for texture development in Bi2Te3.

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ENHANCED PIEZOELECTRIC PROPERTIES IN (Bi0.5K0.5)TiO3–(Bi0.5Na0.5)TiO3 FERROELECTRIC SINGLE CRYSTALS

Journal of Advanced Dielectrics ◽

10.1142/s2010135x11000082 ◽

2011 ◽

Vol 01 (01) ◽

pp. 63-69 ◽

Cited By ~ 7

Author(s):

AKIFUMI MORISHITA ◽

YUUKI KITANAKA ◽

MAKOTO IZUMI ◽

YUJI NOGUCHI ◽

MASARU MIYAYAMA

Keyword(s):

Phase Diagram ◽

Single Crystals ◽

Diffraction Data ◽

Piezoelectric Properties ◽

Rietveld Analysis ◽

X Ray Diffraction ◽

Flux Method ◽

X Ray ◽

Piezoelectric Strain ◽

Piezoelectric Strain Constant

Single crystals of x( Bi,K ) TiO 3 - (1 - x)( Bi,Na ) TiO 3 (0.11 ≤ x ≤ 0.47) were grown by a flux method and their polarization and piezoelectric properties were investigated along 〈100〉 cubic at 25°C. Rietveld analysis of powder X-ray diffraction data provides a tentative phase diagram in this system: rhombohedral R3c for x ≤ 0.22, pseudocubic for 0.22 < x < 0.3 and tetragonal P4mm for 0.3 ≤ x. Piezoelectric strain properties show that the crystals (x = 0.38) exhibited an extremely large piezoelectric strain constant of 637 pm/V.

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Structure of AFeTi(PO4)3 (A=Ca,Cd) Nasicon phases from powder X-ray data

Powder Diffraction ◽

10.1154/1.1604127 ◽

2004 ◽

Vol 19 (2) ◽

pp. 157-161 ◽

Cited By ~ 6

Author(s):

Abderrahim Aatiq ◽

Hicham Dhoum

Keyword(s):

Solid State ◽

Diffraction Data ◽

Solid State Reaction ◽

Rietveld Analysis ◽

Nasicon Structure ◽

X Ray Diffraction ◽

Hexagonal Cell ◽

X Ray ◽

Cell Parameters ◽

Anion Distance

AFeTi(PO4)3 (A=Ca,Cd) materials were obtained by solid state reaction in air at 1000 °C. Structures of the two compounds were determined from X-ray diffraction data using Rietveld analysis. Both phases exhibit the Nasicon-type structure (R3¯c space group) with a statistical Fe(Ti) distribution within the framework. Their hexagonal cell parameters are a=8.518(1) Å, c=21.797(2) Å and a=8.534(1) Å, c=21.416(2) Å, for CaFeTi(PO4)3 and CdFeTi(PO4)3, respectively. Cd atoms occupy the M1 site in CdFeTi(PO4)3. From XRD data, it is difficult to distinguish without ambiguity between Ca2+ and Ti4+ ions in CaFeTi(PO4)3. Nevertheless from the cation–anion distance found after the structure determination, Ca2+ distribution within the M1 site of Nasicon structure are validated.

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Effect of Mechanical Activation on the Morphology and Microstructure of Ni-Al-Ti-B Composite Powders

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.353-358.1259 ◽

2007 ◽

Vol 353-358 ◽

pp. 1259-1262

Author(s):

Guo Jian Cao ◽

Lin Geng ◽

Yong Liang Guo ◽

Masaaki Naka

Keyword(s):

Particle Size ◽

Mechanical Activation ◽

Weight Ratio ◽

Milling Process ◽

X Ray Diffraction ◽

Composite Powders ◽

Atom Ratio ◽

X Ray ◽

Calculation Results ◽

Effective Grain Size

In this work, Ni-Al-Ti-B composite powders with Ni: Al: Ti: B atom ratio of 5.7: 1.9:1:1 were prepared by using mechanical activation (MA) method. The MA processes were performed by vibration ball mill in a water-cooled chamber for 30 h. The ball-to-powder weight ratio was 10:1. In order to reduce the oxidation of the powders during milling process, ball milling was performed under an Argon atmosphere. The evolution of morphology and microstructure of Ni-Al-Ti-B composite powders were examined at different milling stages using scanning electron microscope and X-ray diffraction. Distribution of powders size was analyzed and the results showed that there were three stages for the change of powders size: (1) at the first stage, powders size increased due to more welding than fracture of the powders within 2h of MA, (2) at the second stage, particle size continuously decreased until 16h of MA due to more fracturing than welding, and (3) after 16h of MA, the particle size remained constant when welding and fracture reached an equilibrium. Calculation results according to Scherrer equation from X-ray pattern showed that the effective grain size continuously decreased with MA time. X-ray diffraction pattern confirmed that the formation of Ni and Ti solid solution during MA process of the Ni-Al-Ti-B composite powders.

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Powder X-ray data for adenosine C10H13N5O4

Powder Diffraction ◽

10.1017/s0885715600010940 ◽

2000 ◽

Vol 15 (2) ◽

pp. 112-115 ◽

Cited By ~ 2

Author(s):

Ruggero Caminiti ◽

Giancarlo Ortaggi ◽

Raffaele Antonio Mazzei ◽

Paolo Ballirano ◽

Rita Rizzi

Keyword(s):

Diffraction Data ◽

Rietveld Analysis ◽

Monoclinic Space Group ◽

Angular Range ◽

X Ray Diffraction ◽

Space Group ◽

X Ray ◽

Cell Parameters ◽

Better Than

New powder X-ray diffraction data of adenosine C10H13N5O4 were reported: cell parameters are a=4.8386(4) Å, b=10.2919(4) Å, c=11.8555(4) Å, β=99.298(5)°, volume 582.63(4)Å for the monoclinic space group P21. The strongest lines are: 7.723 (100), 5.085 (50), 5.851 (45), 4.710 (11), 3.881 (10), 3.899 (9), 3.292 (9), and 3.261 (9). Reported intensities are validated by Rietveld analysis. The data consist of measured positions and intensities and cover an angular range up to 75° 2θ and are significantly better than PDF 35-1977. Experimental, calculated, and difference patterns are also reported.

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Quantitative Phase Abundance in Mg-PSZ by Rietveld Analysis of Neutron and X-Ray Diffraction Data

Materials Science Forum ◽

10.4028/www.scientific.net/msf.34-36.159 ◽

1991 ◽

Vol 34-36 ◽

pp. 159-163 ◽

Cited By ~ 6

Author(s):

R.J. Hill ◽

C.J. Howard ◽

B.E. Reichert

Keyword(s):

Diffraction Data ◽

Rietveld Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Quantitative Phase

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Powder X-ray data for melatonin C13H16N2O2

Powder Diffraction ◽

10.1017/s0885715600010939 ◽

2000 ◽

Vol 15 (2) ◽

pp. 108-111 ◽

Cited By ~ 5

Author(s):

Ruggero Caminiti ◽

Giancarlo Ortaggi ◽

Raffaele Antonio Mazzei ◽

Paolo Ballirano ◽

Rita Rizzi

Keyword(s):

Diffraction Data ◽

Cell Parameter ◽

Rietveld Analysis ◽

Angular Range ◽

X Ray Diffraction ◽

Space Group ◽

X Ray ◽

Powder Diffractometer ◽

Monoclinic Cell

Powder X-ray diffraction data of melatonin C13H16N2O2 were collected on a conventional X-ray powder diffractometer: the monoclinic cell parameter are a=7.7416(8) Å, b=9.2897(9) Å, c=17.1444(16) Å, β=96.756(9)°, volume 1224.4(3) Å3 (space group P21/c). The strongest lines are (d (Å), I/I0) 8.161 (100), 5.411 Å (46), 3.412 Å (34), 4.668 Å (33), 4.645 Å (25), 3.554 Å (22), 3.668 Å (16), and 4.483 Å (14). Reported intensities are validated by Rietveld analysis. The data consist of measured positions and intensities and cover an angular range up to 60° 2θ: experimental, calculated, and difference patterns are also reported.

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