High-Temperature XRD Analysis of Polymers

Microstructural evolution of bond coat with thermal cycling was characterized with transmission electron microscopy (TEM) and high temperature X-ray diffraction (HT-XRD) analysis. Before thermal cycling, the structure of asfabricated bond coat was confirmed to be a long-range ordered B2 β-phase. After thermal cycling to ∼28% of the cyclic life, the bond coat was found to transform into a Nirich L10 martensite (M) from its original B2 structure. The transformations, M ↔ B2, were demonstrated to be reversible and to occur on heating and cooling in each cycle. Quantitative high temperature XRD measurements verified the phase transformations produce about 0.7 % transformation strain. Finite element calculations incorporating the transformation strain indicate that the mertensitic transformation significantly influences the development of stresses and strains in TBC systems.

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High-Temperature XRD Analysis of Polymers

Advances in X-ray Analysis ◽

10.1154/s0376030800014774 ◽

1990 ◽

Vol 34 ◽

pp. 459-463

Author(s):

Robert W. Green

Keyword(s):

High Temperature ◽

Temperature Control ◽

Polymeric Materials ◽

Xrd Analysis ◽

Sample Temperature ◽

X Ray Diffraction ◽

X Ray ◽

High Temperature Xrd ◽

Insight Into

High-temperature x-ray diffraction has many applications. Applied to polymeric materials it is a useful tool for investigating changes in crystallinity, providing insight into molding and extrusion problems, and for examining solvent-resistancy problems. An example of the increasing crystailine character of a polymer as a function of temperature can be seen in figure 1. Diffraction scans at 25°C, 100°C, 150°C, and 200°C clearly show the increasing crystalline character of the potymer with an increase in temperature. Control of sample temperature for a polymer is very important, when analyzing under air, because a momentary overshoot in temperature may lead to the sample igniting. High-temperature investigations of polymers are also subject to the problem of the sample warping and bowing.

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On the Formation of Nanograined LiCo2O3(OH) Spinel-Type Material Synthesized via Modified Low-Temperature Sol-Gel Approach

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1119.106 ◽

2015 ◽

Vol 1119 ◽

pp. 106-110

Author(s):

Rinlee Butch M. Cervera ◽

Shu Yamaguchi

Keyword(s):

High Temperature ◽

Low Temperature ◽

Spinel Structure ◽

Sol Gel ◽

Xrd Analysis ◽

X Ray Diffraction ◽

Spinel Type ◽

Selected Area Electron Diffraction ◽

High Temperature Xrd ◽

Average Grain Size

A new lithium cobalt oxyhydroxide compound has been successfully synthesized. This new compound has been found to be related to the low temperature LiCoO2 (LT-LiCoO2) spinel structure formed at low processing temperatures. With the use of a modified sol-gel approach, this compound with the composition of LiCo2O3(OH) can be successfully synthesized at around 150 °C. Structural analyses using powder X-ray diffraction (XRD) and selected area electron diffraction (SAED) suggest a cubic-spinel structure, which is also supported by FT-IR and TG/DTA analyses. In addition, from the TEM morphological analysis, a very fine nanograined LiCo2O3(OH) powder with an average grain size of 5 nm has been obtained. From these results, the presence of OH or water at low processing temperatures promotes a favorable formation of this structure. At higher temperatures (>400 °C), the phase transforms to a layered high-temperature LiCoO2 (HT-LiCoO2) structure with the excess cobalt precipitated as Co3O4 as suggested by the in-situ high temperature XRD analysis.

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In-Situ Study of Gaseous Reduction of Magnetite Doped with Alumina Using High-Temperature XRD Analysis

Metallurgical and Materials Transactions B ◽

10.1007/s11663-015-0437-4 ◽

2015 ◽

Vol 46 (6) ◽

pp. 2564-2572 ◽

Cited By ~ 5

Author(s):

Yury Kapelyushin ◽

Yasushi Sasaki ◽

Jianqiang Zhang ◽

Sunkwang Jeong ◽

Oleg Ostrovski

Keyword(s):

High Temperature ◽

Xrd Analysis ◽

In Situ Study ◽

Gaseous Reduction ◽

High Temperature Xrd

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In Situ XRD Study of Zirconia Phase Transformation Produced from Chemical and Mineral Processes

Materials Science Forum ◽

10.4028/www.scientific.net/msf.840.375 ◽

2016 ◽

Vol 840 ◽

pp. 375-380

Author(s):

Meor Yusoff Meor Sulaiman ◽

Khaironie Mohamed Takip ◽

Ahmad Khairulikram Zahari

Keyword(s):

High Temperature ◽

Heating Temperature ◽

Tetragonal Zirconia ◽

Amorphous Structure ◽

High Temperature Phase ◽

Temperature Phase ◽

Zirconyl Chloride ◽

High Temperature Xrd ◽

Temperature Phase Transition

The high temperature phase transition of zirconia produced from commercial zirconyl chloride chemical was compared with that produced from a Malaysian zircon mineral. Zirconyl chloride was produced from zircon by using the hydrothermal fusion method. Initial XRD diffractogram of these samples at room temperature show that they are of amorphous structure. High temperature XRD studies was then performed on these samples; heated up to 1500°C. The XRD diffractograms shows that the crystalline structure of tetragonal zirconia was first observed and the monoclinic zirconia becomes more visible at higher heating temperature.

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High temperature XRD on silver sheathed Bi(Pb)-2223 tapes in different oxygen partial pressures

Superconductor Science and Technology ◽

10.1088/0953-2048/11/8/011 ◽

1998 ◽

Vol 11 (8) ◽

pp. 777-780 ◽

Cited By ~ 10

Author(s):

J Müller ◽

J H Albering ◽

B Fischer ◽

S Kautz ◽

P Herzog

Keyword(s):

High Temperature ◽

Partial Pressures ◽

High Temperature Xrd

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Simultaneous Measurement of Temperature and Refractive Index Using High Temperature Resistant Pure Quartz Grating Based on Femtosecond Laser and HF Etching

Materials ◽

10.3390/ma14041028 ◽

2021 ◽

Vol 14 (4) ◽

pp. 1028

Author(s):

Na Zhao ◽

Qijing Lin ◽

Kun Yao ◽

Fuzheng Zhang ◽

Bian Tian ◽

...

Keyword(s):

Refractive Index ◽

High Temperature ◽

Femtosecond Laser ◽

Optical Fiber ◽

Temperature Response ◽

High Sensitivity ◽

Xrd Analysis ◽

Refractive Index Sensor ◽

Compact Structure ◽

Fluid Analysis

The optical fiber temperature and refractive index sensor combined with the hollow needle structure for medical treatment can promote the standardization of traditional acupuncture techniques and improve the accuracy of body fluid analysis. A double-parameter sensor based on fiber Bragg grating (FBG) is developed in this paper. The sensor materials are selected through X-ray diffraction (XRD) analysis, and the sensor sensing principle is theoretically analyzed and simulated. Through femtosecond laser writing pure silica fiber, a high temperature resistant wavelength type FBG temperature sensor is obtained, and the FBG is corroded by hydrofluoric acid (HF) to realize a high-sensitivity intensity-type refractive index sensor. Because the light has dual characteristics of energy and wavelength, the sensor can realize simultaneous dual-parameter sensing. The light from the lead-in optical fiber is transmitted to the sensor and affected by temperature and refractive-index; then, the reflection peak is reflected back to the lead-out fiber by the FBG. The high temperature response and the refractive index response of the sensor were measured in the laboratory, and the high temperature characteristics of the sensor were verified in the accredited institute. It is demonstrated that the proposed sensor can achieve temperature sensing up to 1150 °C with the sensitivity of 0.0134 nm/°C, and refractive sensing over a refractive range of 1.333 to 1.4027 with the sensitivity of −49.044 dBm/RIU. The sensor features the advantages of two-parameter measurement, compact structure, and wide temperature range, and it exhibits great potential in acupuncture treatment.

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Temperature Dependence of Mechanical, Electrical Properties and Crystal Structure of Polyethylene Blends for Cable Insulation

Materials ◽

10.3390/ma11101922 ◽

2018 ◽

Vol 11 (10) ◽

pp. 1922 ◽

Cited By ~ 11

Author(s):

Lunzhi Li ◽

Lisheng Zhong ◽

Kai Zhang ◽

Jinghui Gao ◽

Man Xu

Keyword(s):

High Temperature ◽

Electrical Properties ◽

Temperature Dependence ◽

Elevated Temperatures ◽

Breakdown Strength ◽

Temperature Stability ◽

Xrd Analysis ◽

Insulation Material ◽

Cable Insulation ◽

Polyethylene Blends

There is a long-standing puzzle concerning whether polyethylene blends are a suitable substitution for cable-insulation-used crosslinking polyethylene (XLPE) especially at elevated temperatures. In this paper, we investigate temperature dependence of mechanical, electrical properties of blends with 70 wt % linear low density polyethylene (LLDPE) and 30 wt % high density polyethylene (HDPE) (abbreviated as 70 L-30 H). Our results show that the dielectric loss of 70 L-30 H is about an order of magnitude lower than XLPE, and the AC breakdown strength is 22% higher than XLPE at 90 °C. Moreover, the dynamic mechanical thermal analysis (DMA) measurement and hot set tests suggest that the blends shows optimal mechanical properties especially at high temperature with considerable temperature stability. Further scanning electron microscope (SEM) observation and X-ray diffraction (XRD) analysis uncover the reason for the excellent high temperature performance and temperature stability, which can be ascribed to the uniform fine-spherulite structure in 70 L-30 H blends with high crystallinity sustaining at high temperature. Therefore, our findings may enable the potential application of the blends as cable insulation material with higher thermal-endurance ability.

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