Effect of Cr and Re on the Oxidation Resistance of Ni3Al-Base Single Crystal Alloy IC21 at 1100

2013 ◽  
Vol 747-748 ◽  
pp. 582-587 ◽  
Author(s):  
Xiao Jing Xu ◽  
Qiong Wu ◽  
Sheng Kai Gong ◽  
Shu Suo Li
Keyword(s):  
Electron Microscopy ◽  
Single Crystal ◽  
Oxidation Resistance ◽  
Oxidation Kinetic ◽  
Oxide Scales ◽  
X Ray Diffraction ◽  
Scale Spallation ◽  
X Ray ◽  
Oxidation Properties ◽  
Scanning Electron

The oxidation kinetic curves of three Ni3Al-based single crystal alloys (IC21, IC21C and IC21CR) with different Cr and Re content were examined at 1100. The microstructures and element distributions of the oxide scales on these alloys were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray spectrometry (EDS). Results revealed that the oxidation resistance of these alloys was improved in the order of IC21 < IC21C < IC21CR. The oxide products of IC21 mainly consisted of NiO, α-Al2O3, NiAl2O4and a small amount of NiMoO4and MoO2. The volatilization of Mo oxides led to the oxide scale spallation from IC21C, thus deteriorated the oxidation properties. While for IC21C and IC21CR, the oxidation resistance was significantly improved. The Mo oxides in the oxide layer were greatly reduced and a continuous α-Al2O3layer was formed.

Study on Oxidation Resistance of Ti1-xAlxN Coating

2012 ◽  
Vol 534 ◽  
pp. 97-100
Author(s):  
C.L. Zhong ◽  
P.A. Wei ◽  
L.E. Luo
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Oxidation Resistance ◽  
Reactive Magnetron ◽  
X Ray Diffraction ◽  
X Ray ◽  
Al Content ◽  
Compound Coating ◽  
Cubic Structure ◽  
Scanning Electron

A series of Ti1-xAlxN coatings were deposited by reactive magnetron sputtering. The content, microstructure and surface morphology of the coatings were characterized by energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of Al content on the microstructure and the oxidation resistance was studied. It was found that Ti1-xAlxN compound coating exhibits a cubic structure with (1 1 1) preferred orientations. The oxidation resistance obviously improves with the increase of Al content.

The Structure and Thermal Properties of ZrAlYN Films Deposited by Magnetron Sputtering

2014 ◽  
Vol 488-489 ◽  
pp. 9-13
Author(s):  
Guang Xian ◽  
Hai Bo Zhao ◽  
Hong Yuan Fan ◽  
Hao Du
Keyword(s):  
Electron Microscopy ◽  
Thermal Properties ◽  
Magnetron Sputtering ◽  
Oxidation Resistance ◽  
Solution Phase ◽  
Solid Solution Phase ◽  
Flow Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Scanning Electron

ZrAlYN films were prepared by magnetron sputtering at various N2/Ar flow ratio. The structure, composition and thermal properties were characterized by X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectrum. The results show that the deposited ZrAlN and ZrAlYN films possessed a single NaCl-type solid solution phase. The ZrAlN film was (200) strongly predominated. The (111) peak was prominently increased in ZrAlYN films and thus the preferred orientation changed to (111) and (200) co-predomination. The crystallinity of ZrAlYN films was gradually degraded with enhanced N2/Ar flow ratio. Both ZrAlN and ZrAlYN films were exhibited a featureless fracture microstructure. The thickness of ZrAlYN films was consistently reduced due to more nitride produced on the surface of targets at higher N2/Ar flow ratio. The ZrAlYN films deposited at 1:5 N2/Ar flow ratio was proved to be the best oxidation resistance under annealing at 1000°C for 2h in air. As N2/Ar flow ratio increased, the oxidation resistance of films was inversely deteriorated due to the decreased yttrium content in films.

The Oxidation Resistance of Cu-Ag Alloy Nanopowders Prepared by Induction Plasma Technology

2012 ◽  
Vol 151 ◽  
pp. 28-31 ◽  
Author(s):  
Min Ming Zou ◽  
Mi Yan ◽  
Fu Jun Shang ◽  
Wei Huang ◽  
Yong Liu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Oxidation Resistance ◽  
Average Diameter ◽  
Processing Parameters ◽  
X Ray Diffraction ◽  
Plasma Technology ◽  
Induction Plasma ◽  
X Ray ◽  
Suitable Processing ◽  
Scanning Electron

The Cu-30wt%Ag alloy nanopowders are prepared by induction plasma technology, and the nanopowder is successfully coated by terpineol (C10H18O). The morphology, phase composition and oxidation resistance of nanopowders are characterized by scanning electron microscopy (SEM), X-ray diffraction and thermogravimetric (TG) analysis. When the suitable processing parameters of induction plasma are chosen, the spherical morphology and average diameter about 89 nm of Cu-30wt%Ag nanopowders are obtained. Meanwhile, the Cu-Ag alloy nanopowders which are coated by terpineol are free from oxidation when temperature is below 280°C.

Effects of Cr and Al on High Temperature Oxidation Resistance of Nb-Si System Intermetallics

2007 ◽  
Vol 546-549 ◽  
pp. 1485-1488 ◽  
Author(s):  
Shi Yu Qu ◽  
Ya Fang Han ◽  
Jin Xia Song ◽  
Yong Wang Kang
Keyword(s):  
Electron Microscopy ◽  
High Temperature ◽  
Oxide Scale ◽  
Oxidation Resistance ◽  
High Temperature Oxidation ◽  
Oxidation Products ◽  
X Ray Diffraction ◽  
Temperature Oxidation ◽  
X Ray ◽  
Scanning Electron

The effects of Cr and Al on high temperature oxidation resistance of Nb-Si system intermetallics have been investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD) and weight gain method. The results showed that the high temperature oxidation resistance can be substantially improved by proper Cr or Al addition. The further analysis revealed that Cr promotes the formation of CrNbO4 in scale and improve the adherence between the oxide scale and the substrate. It also found that Al improves the surface morphology of oxide scale and changes oxidation products by promoting the AlNbO4 formation.

Microstructure and Oxidation Resistance of Cr1-xAlxN Coating

2012 ◽  
Vol 531 ◽  
pp. 23-26
Author(s):  
C.L. Zhong ◽  
L.E. Luo
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Oxidation Resistance ◽  
Reactive Magnetron ◽  
X Ray Diffraction ◽  
X Ray ◽  
Al Content ◽  
Compound Coating ◽  
Cubic Structure ◽  
Scanning Electron

A series of Cr1-xAlxN coatings were deposited by reactive magnetron sputtering. The content, microstructure and surface morphology of the coatings were characterized by energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The effect of Al content on the microstructure, and the oxidation resistance and hardness was studied. It was found that Cr1-xAlxN compound coating exhibits a cubic structure with (1 1 1) preferred orientations. The oxidation resistance obviously improves with the increase of Al content.

Formation of Single Crystal Nanowires of GaN on the Si Substrates

2005 ◽  
Vol 475-479 ◽  
pp. 4175-4178 ◽  
Author(s):  
Cheng Shan Xue ◽  
Zhi Hua Dong ◽  
Hui Zhao Zhuang ◽  
Haiyong Gao ◽  
Yi'an Liu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Single Crystal ◽  
Photoelectron Spectroscopy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Si Substrates ◽  
Transmission Electron ◽  
Scanning Electron ◽  
Sputtering System

An extreme thin SiC buffer and Ga2O3 layer were deposited on silicon substrate sequentially with a r.f. magnetron sputtering system. Then the sample was annealed in the ambiance of ammonia at high temperature. Nanowires were found when the sample was tested with scanning electron microscopy (SEM). The composition of the nanowires is found to be GaN when the sample was tested with X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). A nanowire was observed with transmission electron microscopy and it was even and uniform, with diameter of about 60nm. And the nanowire can be testified of wurtzite single crystal structure by electron diffraction (ED) analysis attached to the TEM. The high-resolution transmission electron microscopy (HRTEM) analysis to the nanowire indicates that the nanowire was single crystal with very good quality.

Electron Microscopy of Shock Loaded Polycrystalline Beryllium

1974 ◽  
Vol 32 ◽  
pp. 506-507 ◽  
Author(s):  
J. M. Galbraith ◽  
L. E. Murr ◽  
A. L. Stevens
Keyword(s):  
Electron Microscopy ◽  
Wave Propagation ◽  
Structural Change ◽  
Single Crystal ◽  
Diffraction Pattern ◽  
Shock Loading ◽  
Slip Systems ◽  
Compression Tests ◽  
X Ray Diffraction ◽  
X Ray

Uniaxial compression tests and hydrostatic tests at pressures up to 27 kbars have been performed to determine operating slip systems in single crystal and polycrystal1ine beryllium. A recent study has been made of wave propagation in single crystal beryllium by shock loading to selectively activate various slip systems, and this has been followed by a study of wave propagation and spallation in textured, polycrystal1ine beryllium. An alteration in the X-ray diffraction pattern has been noted after shock loading, but this alteration has not yet been correlated with any structural change occurring during shock loading of polycrystal1ine beryllium.This study is being conducted in an effort to characterize the effects of shock loading on textured, polycrystal1ine beryllium. Samples were fabricated from a billet of Kawecki-Berylco hot pressed HP-10 beryllium.

Identification of calcium oxalate crystals in dried or fixed tobacco leaf

1984 ◽  
Vol 42 ◽  
pp. 288-289
Author(s):  
Vicki L. Baliga ◽  
Mary Ellen Counts
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Calcium Oxalate ◽  
Growth And Development ◽  
Polarized Light ◽  
Calcium Oxalate Crystals ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

Calcium is an important element in the growth and development of plants and one form of calcium is calcium oxalate. Calcium oxalate has been found in leaf seed, stem material plant tissue culture, fungi and lichen using one or more of the following methods—polarized light microscopy (PLM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray diffraction.Two methods are presented here for qualitatively estimating calcium oxalate in dried or fixed tobacco (Nicotiana) leaf from different stalk positions using PLM. SEM, coupled with energy dispersive x-ray spectrometry (EDS), and powder x-ray diffraction were used to verify that the crystals observed in the dried leaf with PLM were calcium oxalate.

Environmental scanning electron microscopy of fresh human gallstones reveals new morphologies of precipitated calcium salts

1992 ◽  
Vol 50 (2) ◽  
pp. 1322-1323
Author(s):  
Howard S. Kaufman ◽  
Keith D. Lillemoe ◽  
John T. Mastovich ◽  
Henry A. Pitt
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Environmental Scanning Electron Microscopy ◽  
Environmental Scanning ◽  
X Ray Diffraction ◽  
Calcium Salts ◽  
Cholesterol Gallstones ◽  
X Ray ◽  
Ca Carbonate ◽  
Scanning Electron

Gallstones contain precipitated cholesterol, calcium salts, and proteins. Calcium (Ca) bilirubinate, palmitate, phosphate, and carbonate occurring in gallstones have variable morphologies but characteristic windowless energy dispersive x-ray (EDX) spectra. Previous studies of gallstone microstructure and composition using scanning electron microscopy (SEM) with EDX have been limited to dehydrated samples. In this state, Ca bilirubinates appear as either glassy masses, which predominate in black pigment stones, or as clusters, which are found mostly in cholesterol gallstones. The three polymorphs of Ca carbonate, calcite, vaterite, and aragonite, have been identified in gallstones by x-ray diffraction, however; the morphologies of these crystals vary in the literature. The purpose of this experiment was to study fresh gallstones by environmental SEM (ESEM) to determine if dehydration affects gallstone Ca salt morphology.Gallstones and bile were obtained fresh at cholecystectomy from 6 patients. To prevent dehydration, stones were stored in bile at 37°C. All samples were studied within 4 days of procurement.

Photocatalytic activity of TiO2 synthesized by anodization and anodic spark deposition

MRS Advances ◽  
2020 ◽  
Vol 5 (61) ◽  
pp. 3141-3152
Author(s):  
Alma C. Chávez-Mejía ◽  
Génesis Villegas-Suárez ◽  
Paloma I. Zaragoza-Sánchez ◽  
Rafael Magaña-López ◽  
Julio C. Morales-Mejía ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Surface Characteristics ◽  
Amorphous Solids ◽  
X Ray Diffraction ◽  
X Ray ◽  
Catalytic Activities ◽  
Anodic Spark Oxidation ◽  
Porous Surfaces ◽  
Scanning Electron

AbstractSeveral photocatalysts, based on titanium dioxide, were synthesized by spark anodization techniques and anodic spark oxidation. Photocatalytic activity was determined by methylene blue oxidation and the catalytic activities of the catalysts were evaluated after 70 hours of reaction. Scanning Electron Microscopy and X Ray Diffraction analysis were used to characterize the catalysts. The photocatalyst prepared with a solution of sulfuric acid and 100 V presented the best performance in terms of oxidation of the dye (62%). The electric potential during the synthesis (10 V, low potential; 100 V, high potential) affected the surface characteristics: under low potential, catalyst presented smooth and homogeneous surfaces with spots (high TiO2 concentration) of amorphous solids; under low potential, catalyst presented porous surfaces with crystalline solids homogeneously distributed.

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