scholarly journals Revealing tetragonal-to-monoclinic phase transformation in Y-TZP at an initial stage of low temperature degradation using grazing incident-angle X-ray diffraction measurement

2018 ◽  
Vol 126 (9) ◽  
pp. 728-731
Author(s):  
Tsukasa Koyama ◽  
Akihito Kumamoto ◽  
Koji Matsui ◽  
Yuichi Ikuhara ◽  
Hidehiro Yoshida
Keyword(s):  
Phase Transformation ◽  
Low Temperature ◽  
Monoclinic Phase ◽  
Incident Angle ◽  
Diffraction Measurement ◽  
X Ray Diffraction ◽  
X Ray ◽  
Initial Stage

Displacive Phase Transformation in Vanadium - Substituted Lanthanum Niobate

1983 ◽  
Vol 24 ◽  
Author(s):  
A. T. Aldred ◽  
S.-K. Chan ◽  
M. H. Grimsditch ◽  
M. V. Nevitt
Keyword(s):  
Phase Transformation ◽  
High Temperature ◽  
Low Temperature ◽  
Raman Scattering ◽  
Transformation Temperature ◽  
Complex Oxides ◽  
Temperature Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
First Order

ABSTRACTThe displacive transformations in complex oxides of the type LaNb1-xVxO4 has been studied by x-ray diffraction and Raman scattering for 0 < x < 0.3. X-ray diffraction results indicate that the transformation from the tetragonal high temperature structure (C4h6) to the monoclinic low-temperature structure (C2h6) is higher than first order and that the transformation temperature Tc is depressed significantly by V substitution. Raman scattering results show that the force constant between the nearest (Nb, V)O4 tetrahedral units behave uniquely compared to others. It softens at Tc as a function of composition and it also softens as a function of temperature as Tc is approached from above.

In-Situ X-Ray Diffraction Studies On Lithium- Ion Battery Cathodes

1999 ◽  
Vol 575 ◽  
Author(s):  
Mark A. Rodriguez ◽  
David Ingersoll ◽  
Daniel H. Doughty
Keyword(s):  
Phase Transformation ◽  
Monoclinic Phase ◽  
Hexagonal Lattice ◽  
Lithium Ion ◽  
Hexagonal Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Co Doping ◽  
In Situ Xrd

ABSTRACTLiNi0.8Co0.2O2 and LiNiO2 have been characterized in-situ XRD. LiNi0.8Co0.2O2 does not undergo a monoclinic phase transformation but remains a hexagonal lattice throughout the entire charging cycle. It is hypothesized that Co-doping may help stabilize the hexagonal structure.

Charles S. Barrett: X-Ray Metallurgist — An Informal Portrait

1987 ◽  
Vol 2 (3) ◽  
pp. 163-175
Author(s):  
R. N. Rose
Keyword(s):  
Physical Chemistry ◽  
Phase Transformation ◽  
Low Temperature ◽  
First Principles ◽  
Atomic Level ◽  
X Ray Diffraction ◽  
Wide Audience ◽  
X Ray

Charles Barrett's work in phase transformation at the atomic level helped redefine the underpinnings of the science and practice of metallurgy. His work in low temperature physical chemistry has extended its range. And, perhaps more than anyone else, as a teacher and author, he has helped introduce the technique of X-ray diffraction to the present generations of practicing metallurgists.The relevance of his contributions is demonstrated by the continuing utility of his widely translated metallurgical text, Structure of Metals, which, when it first appeared, made the understanding of metallurgy at the atomic level accessible to a wide audience. Today this book has become a compendium of first principles.

NANO-VANADIUM DOPING-DRIVEN LOW TEMPERATURE STRUCTURAL PHASE TRANSFORMATION IN TITANIA

2009 ◽  
Vol 23 (29) ◽  
pp. 3543-3549
Author(s):  
ANUJ KUMAR ◽  
BHASKER GAHTORI ◽  
NEERAJ KUMAR ◽  
V. P. S. AWANA ◽  
A. K. SRIVASTAVA ◽  
...  
Keyword(s):  
Phase Transformation ◽  
Low Temperature ◽  
Structural Phase ◽  
Rutile Phase ◽  
Vanadium Content ◽  
Scanning Electron Micrographs ◽  
X Ray Diffraction ◽  
X Ray ◽  
Heat Treated ◽  
Vanadium Doping

Synthesis, X-ray diffraction (XRD), morphological, and magnetization studies of nano-vanadium doped TiO 2 are reported here. Commercially available anatase nano- TiO 2 and nano-vanadium powders were mixed and heat-treated in air at 600°C. X-ray diffraction revealed a complete anatase to rutile phase transformation at low vanadium content of 5%. Samples annealed under different environments such as Ar and O 2 also exhibited the same trend. Such a phase transformation at relatively low temperature (600°C) has been explained based on enhanced reactivity between vanadium and TiO 2 powders. Scanning electron micrographs elucidated the tunable microstructures from irregular-shaped, in the pristine TiO 2 (x=0.0), to well-faceted polyhedra V-doped (x=0.05 to 0.15) samples. Room temperature magnetization results revealed that upto 10% vanadium doping the samples are diamagnetic in nature and exhibit a paramagnetic transition for higher V content which presumably can be attributed to the presence of vanadium pentaoxide observed in the XRD.

scholarly journals Influence of Manufacturing Regimes on the Phase Transformation of Dental Zirconia

Materials ◽  
2021 ◽  
Vol 14 (17) ◽  
pp. 4980
Author(s):  
Markus Wertz ◽  
Hieronymus Hoelzig ◽  
Gert Kloess ◽  
Sebastian Hahnel ◽  
Andreas Koenig
Keyword(s):  
Phase Transformation ◽  
Phase Composition ◽  
Low Temperature ◽  
X Ray Diffraction ◽  
Stabilized Zirconia ◽  
X Ray ◽  
Dental Prostheses ◽  
Alumina Particles ◽  
History Of ◽  
Fixed Dental Prostheses

Background: The influence of typical manufacturing regimes for producing fixed dental prostheses (FDPs) from yttria partly-stabilized zirconia polycrystals (3Y/4Y/5Y-TZP) on the phase composition is quantified. Methods: Fixed dental prostheses (FDPs) were designed using a CAD process and machined from different Y-TZP blanks from two manufacturers differing in yttria contents. Subsequent to sintering, the FDPs were glaze fired and air-blasted using alumina particles. Phase composition was determined with X-ray diffraction and quantified with Rietveld refinement. Results: The blanks from VITA Zahnfabrik (VITA YZ HT, VITA YZ ST, VITA YZ XT) and Dental Direct (DD Bio ZX2, DD cube ONE, DD cube X2) featured a rhombohedral portion with rather small crystallites and a small monoclinic portion for 3Y/4Y-TZPs, which increased after machining and disappeared after sintering. Glaze firing and air-blasting with alumina particles had no significant influence on the phase composition. Conclusion: The phase history of dental zirconia is revealed, which may have implications on further processing and aging of the FDP (e.g. low temperature degradation) in mouth.

Reaction of Dental Zirconia with Phosphate-Bonded Investments for Heat Pressing Technique

2012 ◽  
Vol 529-530 ◽  
pp. 537-542 ◽  
Author(s):  
Kentaro Yoshihara ◽  
Seiji Ban ◽  
Tatsusi Kawai ◽  
Yoshinobu Tanaka
Keyword(s):  
Low Temperature ◽  
Monoclinic Phase ◽  
Diffraction Peak ◽  
X Ray Diffraction ◽  
X Ray ◽  
Different Temperatures ◽  
Diffraction Peaks

The aim of the study was to investigate the reaction of phosphate bonded investment to zirconia during for the heat-pressing technique. Two kinds of dental zirconia were used in this study (inCoris ZI and P-NANOZR). Zirconia was invested into the three kinds of phosphate-bonded investment (Ceravety, PC-15 and Norivest). The investments were fired at several different temperatures. The X-ray diffraction peaks due to monoclinic ZrO2 were not detected on the waxed-up side of zirconia discs. It demonstrates that no low temperature degradation occurred during the heating of the investment. X-ray diffractometry revealed that the peak assigned to ZrP2O7 was detected on the contact side of zirconia discs fired with phosphate-bonded investment at 850 and 950°C. It also revealed that diffraction peak assigned to YPO4 and the monoclinic ZrO2 were detected in the same side of zirconia discs contacted with phosphate-bonded investment fired at 1100 °C. It can be concluded that the reduction of Y caused the transformation from tetragonal to monoclinic phase and the reduction of strength.

Suppressing the Powdering of Zirconia Fibers after High-Temperature Application by Large Additions of Yttria

2011 ◽  
Vol 306-307 ◽  
pp. 1512-1515
Author(s):  
Xian Qin Hou
Keyword(s):  
Phase Transformation ◽  
High Temperature ◽  
Volume Expansion ◽  
Monoclinic Phase ◽  
Sol Gel ◽  
X Ray Diffraction ◽  
High Temperature Application ◽  
X Ray ◽  
Temperature Application ◽  
Scanning Electron

Zirconia fibers with different Y2O3 additions were prepared by sol-gel method. After the fiber was thermally treated at 1650°C for 6h, the microstructure and crystalline phase were investigated by scanning electron microscope and X-ray diffraction. It was found that the fibers with 5mol% of Y2O3 seriously powdered due to volume expansion caused by the phase transformation form tetragonal phase to monoclinic phase. The powdering of zirconia fibers after high–temperature application could be depressed when the amount of Y2O3 was more than 10mol%.

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