Phase Evolution During Sintering of Mullite/zirconia Composites Using Silica-coated Alumina Powders

2000 ◽  
Vol 15 (6) ◽  
pp. 1358-1366 ◽  
Author(s):  
V. Yaroshenko ◽  
D. S. Wilkinson
Keyword(s):  
Energy Barrier ◽  
Lower Energy ◽  
Crystallization Process ◽  
Phase Evolution ◽  
Combined Effects ◽  
Microstructure Development ◽  
Mullite Formation ◽  
Zirconia Composites ◽  
Zircon Formation

Mullite-based composites can be made by an in situ reaction process using silica-coated alumina (SCA) powder as a mullite precursor. In this paper we present the combined effects of zirconia and premullite seeds on the crystallization process and microstructure development. When zirconia is added without seeding, mullite formation proceeds through the formation of transient zircon. This phase provides a lower energy barrier for mullite nucleation and thus lowers the mullitization temperature. The presence of yttria as a stabilizer in zirconia reduces the activation energy for zircon formation and thus promotes the transient reaction. The addition of premullite seeds results in the nucleation of mullite from alumina and silica, and zircon does not form. At low seeding levels mullitization remains nucleation-controlled; however, once the seeding level exceeds 1–2%, this is no longer the case.

Phase evolution during laser In-Situ carbide coating

2005 ◽  
Vol 36 (13) ◽  
pp. 797-803 ◽  
Author(s):  
Anshul Singh ◽  
Narendra B. Dahotre
Keyword(s):  
Phase Evolution ◽  
Carbide Coating

In situ phase evolution of TiO2/Ti3C2T heterojunction for enhancing adsorption and photocatalytic degradation

2021 ◽  
Vol 545 ◽  
pp. 149031
Author(s):  
Huiqi Zheng ◽  
Xiaorong Meng ◽  
Jin Chen ◽  
Meidan Que ◽  
Wendong Wang ◽  
...  
Keyword(s):  
Photocatalytic Degradation ◽  
Phase Evolution

(Invited) Microstructure Development in Epitaxially Grown In Situ Boron and Carbon Co-Doped Strained 60% Silicon-Germanium Layers

2013 ◽  
Vol 50 (9) ◽  
pp. 1013-1024 ◽  
Author(s):  
A. Reznicek ◽  
T. N. Adam ◽  
J. Li ◽  
Z. Zhu ◽  
R. Murphy ◽  
...  
Keyword(s):  
Silicon Germanium ◽  
Microstructure Development ◽  
Co Doped

scholarly journals Crystallization behavior of ion beam sputtered HfO2 thin films and its effect on the laser-induced damage threshold

2021 ◽  
Vol 17 (1) ◽  
Author(s):  
Zoltán Balogh-Michels ◽  
Igor Stevanovic ◽  
Aurelio Borzi ◽  
Andreas Bächli ◽  
Daniel Schachtler ◽  
...  
Keyword(s):  
Activation Energy ◽  
Crystallization Process ◽  
Ion Beam ◽  
Damage Threshold ◽  
High Activation ◽  
Quarter Wave ◽  
Dimensional Growth ◽  
Laser Induced Damage ◽  
Significant Increment

AbstractIn this work, we present our results about the thermal crystallization of ion beam sputtered hafnia on 0001 SiO2 substrates and its effect on the laser-induced damage threshold (LIDT). The crystallization process was studied using in-situ X-ray diffractometry. We determined an activation energy for crystallization of 2.6 ± 0.5 eV. It was found that the growth of the crystallites follows a two-dimensional growth mode. This, in combination with the high activation energy, leads to an apparent layer thickness-dependent crystallization temperature. LIDT measurements @355 nm on thermally treated 3 quarter-wave thick hafnia layers show a decrement of the 0% LIDT for 1 h @773 K treatment. Thermal treatment for 5 h leads to a significant increment of the LIDT values.

Thermal stability and miscibility of co-evaporated methyl ammonium lead halide (MAPbX3, X = I, Br, Cl) thin films analysed by in situ X-ray diffraction

2018 ◽  
Vol 6 (24) ◽  
pp. 11496-11506 ◽  
Author(s):  
Paul Pistor ◽  
Thomas Burwig ◽  
Carlo Brzuska ◽  
Björn Weber ◽  
Wolfgang Fränzel
Keyword(s):  
Thin Films ◽  
Thermal Stability ◽  
Thermal Treatment ◽  
Phase Evolution ◽  
X Ray Diffraction ◽  
Crystalline Phases ◽  
X Ray ◽  
Subsequent Thermal Treatment ◽  
Lead Halide

We present the identification of crystalline phases by in situ X-ray diffraction during growth and monitor the phase evolution during subsequent thermal treatment of CH3NH3PbX3 (X = I, Br, Cl) perovskite thin films.

In situ high temperature optical microscopy study of phase evolution in YBa2Cu3O7−δ films prepared by a fluorine-free sol–gel route

2006 ◽  
Vol 436 (2) ◽  
pp. 62-67 ◽  
Author(s):  
Yulong Zhang ◽  
Xin Yao ◽  
Jie Lian ◽  
Lumin Wang ◽  
Aihua Li ◽  
...  
Keyword(s):  
High Temperature ◽  
Optical Microscopy ◽  
Sol Gel ◽  
Phase Evolution ◽  
Microscopy Study

Crystallization Behavior of Polyethylene/Montmorillonite Nanocomposites Prepared by In Situ Polymerization

2012 ◽  
Vol 184-185 ◽  
pp. 932-935
Author(s):  
Min Li ◽  
Li Guang Xiao ◽  
Hong Kai Zhao
Keyword(s):  
Differential Scanning Calorimetry ◽  
Crystallization Behavior ◽  
Crystallization Process ◽  
In Situ Polymerization ◽  
Nucleating Agent ◽  
Lower Content ◽  
Melting Points ◽  
Scanning Calorimetry ◽  
Montmorillonite Nanocomposites

Polyethylene/montmorillonite (PE/MMT) nanocomposites were prepared by in situ polymerization. The crystallization behavior of PE/MMT nanocomposites at different MMT concentrations (from 0.1 to 1.2 wt %) were investigated by differential scanning calorimetry (DSC). The equilibrium melting points increase by the addition of MMT. The crystallization rates of PE/MMT nanocomposites are faster than those of pure PE. The addition of MMT facilitated the crystallization of PE, with the MMT functioning as a heterogeneous nucleating agent at lower content; at higher concentrations, however, the physical hindrance of the MMT layers to the motion of PE chains retarded the crystallization process.

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