In Situ Study of Zirconia Stabilization by Anion Exchange (N for O) Using High-Temperature, Controlled Atmosphere Electron Diffraction

1999 ◽  
Vol 589 ◽  
Author(s):  
Renu Sharma ◽  
Eberhard Schweda ◽  
Dirk Naedele
Keyword(s):  
High Temperature ◽  
Electron Diffraction ◽  
Anion Exchange ◽  
High Temperatures ◽  
Controlled Atmosphere ◽  
In Situ Study ◽  
Environmental Cell ◽  
Temperature Controlled ◽  
Cubic Structure

AbstractStabilization of zirconia by anion exchange (N for O) is a novel idea. A number of oxy-nitrides with flourite-related (cubic) structure have been reported to form at high temperatures (1100°C). We have used a TEM equipped with environmental cell and Gatan Imaging Filter (GIF) to study the nitridation behavior of zirconia. The in situ observations reveal the formation of a cubic structure at ≈800°C when the Zr(OH) 4×H2O precursor was heated in ≈2 torr of NH3. The presence of N in the lattice is confirmed by electron energyloss spectroscopy.

Unusual irradiation-induced disordering in Cu3Au near the critical temperature: An in situ study using electron diffraction

2018 ◽  
Vol 33 (22) ◽  
pp. 3841-3848
Author(s):  
Calvin Robert Lear ◽  
Robert S. Averback ◽  
Pascal Bellon ◽  
Andrea E. Sand ◽  
Marquis A. Kirk
Keyword(s):  
Critical Temperature ◽  
Electron Diffraction ◽  
In Situ Study ◽  
Image Position

Abstract

scholarly journals High-temperature decomposition of Cu2BaSnS4 with Sn loss reveals newly identified compound Cu2Ba3Sn2S8

2020 ◽  
Vol 8 (22) ◽  
pp. 11346-11353
Author(s):  
José A. Márquez ◽  
Jon-Paul Sun ◽  
Helena Stange ◽  
Hasan Ali ◽  
Leo Choubrac ◽  
...  
Keyword(s):  
High Temperature ◽  
High Temperatures ◽  
Fluorescence Analysis ◽  
Decomposition Mechanism ◽  
Temperature Decomposition

The decomposition mechanism of Cu2BaSnS4 is studied by in situ diffraction and fluorescence analysis revealing “Sn loss” and Cu2Ba3Sn2S8 at high temperatures.

Stability of TaC precipitates in a Co–Re-based alloy being developed for ultra-high-temperature applications

2016 ◽  
Vol 49 (4) ◽  
pp. 1253-1265 ◽  
Author(s):  
Ralph Gilles ◽  
Debashis Mukherji ◽  
Lukas Karge ◽  
Pavel Strunz ◽  
Premysl Beran ◽  
...  
Keyword(s):  
High Temperature ◽  
High Temperatures ◽  
Gas Turbines ◽  
Volume Fraction ◽  
Turbine Blades ◽  
Alloy Development ◽  
Carbide Phases ◽  
Ultra High Temperature ◽  
Temperature Applications

Co–Re alloys are being developed for ultra-high-temperature applications to supplement Ni-based superalloys in future gas turbines. The main goal of the alloy development is to increase the maximum service temperature of the alloy beyond 1473 K,i.e.at least 100 K more than the present single-crystal Ni-based superalloy turbine blades. Co–Re alloys are strengthened by carbide phases, particularly the monocarbide of Ta. The binary TaC phase is stable at very high temperatures, much greater than the melting temperature of superalloys and Co–Re alloys. However, its stability within the Co–Re–Cr system has never been studied systematically. In this study an alloy with the composition Co–17Re–23Cr–1.2Ta–2.6C was investigated using complementary methods of small-angle neutron scattering (SANS), scanning electron microscopy, X-ray diffraction and neutron diffraction. Samples heat treated externally and samples heatedin situduring diffraction experiments exhibited stable TaC precipitates at temperatures up to 1573 K. The size and volume fraction of fine TaC precipitates (up to 100 nm) were characterized at high temperatures within situSANS measurements. Moreover, SANS was used to monitor precipitate formation during cooling from high temperatures. When the alloy is heated the matrix undergoes an allotropic phase transformation from the ∊ phase (hexagonal close-packed) to the γ phase (face-centred cubic), and the influence on the strengthening TaC precipitates was also studied within situSANS. The results show that the TaC phase is stable and at these high temperatures the precipitates coarsen but still remain. This makes the TaC precipitates attractive and the Co–Re alloys a promising candidate for high-temperature application.

High-Temperature Processing of Ba3ZnTa2O9:  an In situ Study Using Synchrotron X-ray Powder Diffraction

2007 ◽  
Vol 19 (19) ◽  
pp. 4731-4740 ◽  
Author(s):  
Phillip M. Mallinson ◽  
John B. Claridge ◽  
Matthew J. Rosseinsky ◽  
Richard M. Ibberson ◽  
Jonathan P. Wright ◽  
...  
Keyword(s):  
High Temperature ◽  
Powder Diffraction ◽  
X Ray ◽  
In Situ Study ◽  
High Temperature Processing
Sign in / Sign up

Export Citation Format

Share Document