An Ultrahigh-Temperature, Single-Crystal Texture Camera Diffractometer*

1964 ◽  
Vol 8 ◽  
pp. 86-90
Author(s):  
Robert L. Prickett
Keyword(s):  
High Temperature ◽  
Single Crystal ◽  
Ion Beam ◽  
Sample Surface ◽  
Refractory Materials ◽  
X Ray ◽  
First Order ◽  
Crystal Texture ◽  
Ultrahigh Temperature ◽  
Electronic Detector

AbstractA single-crystal high-temperature X-ray camera has been built with permissible operating temperatures of 2500°C. The camera is constructed to rest upon a Siemens horizontal diffractometer and may be used with either an external electronic detector or with film. The sample is supported on an externally adjustable goniometer head and is heated from the back by an ion beam. Controlled oscillation allows rotation photographs to be obtained from the sample surface not touched by the ion stream. Temperature is controlled by a thermocouple supporting the sample, the thermocouple being an intrinsic part of the goniometer. As a design limit, zero and first order layer lines with iron Kα. radiation on specimens with lattice parameters of 2.6 Å or larger may be recorded. Copper, cobalt, and molybdenum radiation allow even greater latitude. Types of samples that may be studied include powder (pellet), single crystal, wire, or rod. The camera serves equally well for single-crystal, texture, or powder studies on refractory materials.

The Basic Physical Principles of Ion, Electron, and X-Ray Detectors and Their Application to Microanalysis

1985 ◽  
Vol 43 ◽  
pp. 154-157
Author(s):  
A.J. Tousimis
Keyword(s):  
Ion Beam ◽  
Depth Resolution ◽  
Sample Surface ◽  
High Energy ◽  
X Rays ◽  
X Ray ◽  
Electrons And Ions ◽  
Spatial Depth ◽  
Minimum Surface Area ◽  
Physical Principles

An integral and of prime importance of any microtopography and microanalysis instrument system is its electron, x-ray and ion detector(s). The resolution and sensitivity of the electron microscope (TEM, SEM, STEM) and microanalyzers (SIMS and electron probe x-ray microanalyzers) are closely related to those of the sensing and recording devices incorporated with them.Table I lists characteristic sensitivities, minimum surface area and depth analyzed by various methods. Smaller ion, electron and x-ray beam diameters than those listed, are possible with currently available electromagnetic or electrostatic columns. Therefore, improvements in sensitivity and spatial/depth resolution of microanalysis will follow that of the detectors. In most of these methods, the sample surface is subjected to a stationary, line or raster scanning photon, electron or ion beam. The resultant radiation: photons (low energy) or high energy (x-rays), electrons and ions are detected and analyzed.

Thermal analysis of rare earth gallates and aluminates

1990 ◽  
Vol 5 (1) ◽  
pp. 183-189 ◽  
Author(s):  
H. M. O'Bryan ◽  
P. K. Gallagher ◽  
G. W. Berkstresser ◽  
C. D. Brandle
Keyword(s):  
Thermal Analysis ◽  
Thermal Expansion ◽  
High Temperature ◽  
Superconducting Films ◽  
Czochralski Technique ◽  
X Ray Diffraction ◽  
X Ray ◽  
First Order ◽  
Expansion Matching ◽  
First Order Phase

Dilatometry, high-temperature x-ray diffraction, differential thermal analysis, and differential scanning calorirmetry have been performed on LaGaO3, NdGaO3, PrGaO3, SmAlO3, and LaAlO3 single crystals grown by the Czochralski technique. First order phase transitions have been located at 145°C for LaGaO3 and 785°C for SmAlO3, and ΔH has been measured for the LaGaO3 transition. Second order transitions have been identified for LaGaO3, PrGaO3, NdGaO3, and LaAlO3. The usefulness of these compounds as substrates for high temperature superconducting films is discussed in terms of thermal expansion matching.

Revision of the Li–Si Phase Diagram: Discovery and Single-Crystal X-ray Structure Determination of the High-Temperature Phase Li4.11Si

2013 ◽  
Vol 25 (22) ◽  
pp. 4623-4632 ◽  
Author(s):  
Michael Zeilinger ◽  
Iryna M. Kurylyshyn ◽  
Ulrich Häussermann ◽  
Thomas F. Fässler
Keyword(s):  
Phase Diagram ◽  
High Temperature ◽  
Single Crystal ◽  
Structure Determination ◽  
High Temperature Phase ◽  
Temperature Phase ◽  
X Ray

High-temperature X-ray powder diffraction study of the tetragonal-cubic phase transition in nanocrystalline, compositionally homogeneous ZrO2–CeO2 solid solutions

2008 ◽  
Vol 23 (S1) ◽  
pp. S70-S74 ◽  
Author(s):  
L. M. Acuña ◽  
R. O. Fuentes ◽  
D. G. Lamas ◽  
I. O. Fábregas ◽  
N. E. Walsöe de Reca ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Phase Transition ◽  
High Temperature ◽  
Powder Diffraction ◽  
Solid Solutions ◽  
Tetragonal Phase ◽  
Room Temperature ◽  
Cubic Phase ◽  
X Ray ◽  
First Order

Crystal structure of compositionally homogeneous, nanocrystalline ZrO2–CeO2 solutions was investigated by X-ray powder diffraction as a function of temperature for compositions between 50 and 65 mol % CeO2. ZrO2-50 and 60 mol % CeO2 solid solutions, which exhibit the t′-form of the tetragonal phase at room temperature, transform into the cubic phase in two steps: t′-to-t″ followed by t″-to-cubic. But the ZrO2-65 mol % CeO2, which exhibits the t″-form, transforms directly to the cubic phase. The results suggest that t′-to-t″ transition is of first order, but t″-to-cubic seems to be of second order.

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