Oxidation Resistance of Diffusion Silicide Coatings on Mo and TZM Alloy

Characterization of microstructure of pack cemented silicide coatings based on MoSi2phase was described in this article as well as a short term oxidation resistance of these types of coatings at temperature 1200oC. Silicide coatings were deposited on top surface of Mo and Mo alloys of TZM type by diffusional process of siliconizing in activated powders. Morphology of coatings was characterized by evaluation of chemical and phase’s composition of deposited coatings by EDS and XRD methods respectively. In the case of Mo sheet after diffusion process of siliconizing single layer of MoSi2type was obtained, but in the case of TZM alloy, in the same conditions of process, double layered coating was generated. Thick outer layer was build form MoSi2phase, but very thin internal layer consist Mo5Si3phase. The thicknesses of coatings were ca. 45μm, and were uniform. Morphology of coatings was free from inclusion and contaminations in their cores. The isolated cracks were observed, but their volume was very small. The oxidation test was performed at temperature 1200oC. The specimens were tested at 25, 500 and 100 hours of test. After each period of test characterization of coatings top surface was made. Total destruction of specimens was observed in range between 50 and 100 h of test.

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Structure, mechanical properties and oxidation resistance of MoSi2, MoSiB and MoSiB/SiBC coatings

Izvestiya Vuzov Poroshkovaya Metallurgiya i Funktsional’nye Pokrytiya (Universitiesʹ Proceedings Powder Metallurgy аnd Functional Coatings) ◽

10.17073/1997-308x-2018-3-93-104 ◽

2018 ◽

pp. 93-104

Author(s):

F. V. Kiryukhantsev-Korneev ◽

A. Yu. Potanin

Keyword(s):

Mechanical Properties ◽

Oxidation Resistance ◽

Elastic Recovery ◽

Single Layer ◽

Optical Emission ◽

Protective Film ◽

Short Term ◽

X Ray ◽

Elastoplastic Properties ◽

Lower Oxidation

Magnetron sputtering was used to obtain single-layer MoSi2, MoSiB and multilayer MoSiB/SiBC coatings. Coating structures were studied using X-ray phase analysis, scanning electron microscopy and glow discharge optical emission spectroscopy. Mechanical properties of the coatings were determined by nanoindentation. The coatings were tested for oxidation resistance and thermal stability at temperatures between 600 °С and 1200 °С. It was found that single-layer MoSiB coatings have a hardness of 27 GPa, elasticity modulus of 390 GPa and elastic recovery of 48 % and exhibit short-term oxidation resistance up to 1500 °С inclusive due to a SiO2-based protective film formed on their surfaces. MoSi2coatings have hardness comparable to that of MoSiB but slightly lower oxidation resistance. Multilayer MoSiB/SiBC coatings feature 23–27 GPa hardness and oxidation resistance limited to 1500 °С, but at the same time they have higher elastoplastic properties as compared to MoSiB.

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Characterization of a monolayer graphitic structure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100171535 ◽

1994 ◽

Vol 52 ◽

pp. 760-761

Author(s):

X. Lin ◽

X. K. Wang ◽

V. P. Dravid ◽

J. B. Ketterson ◽

R. P. H. Chang

Keyword(s):

Three Dimensional ◽

Single Layer ◽

Synthesis Process ◽

Graphitic Structure ◽

Positive Gaussian Curvature ◽

Graphitic Sheet ◽

Structural And Electronic Properties ◽

New Material ◽

Hexagonal Network

For small curvatures of a graphitic sheet, carbon atoms can maintain their preferred sp2 bonding while allowing the sheet to have various three-dimensional geometries, which may have exotic structural and electronic properties. In addition the fivefold rings will lead to a positive Gaussian curvature in the hexagonal network, and the sevenfold rings cause a negative one. By combining these sevenfold and fivefold rings with sixfold rings, it is possible to construct complicated carbon sp2 networks. Because it is much easier to introduce pentagons and heptagons into the single-layer hexagonal network than into the multilayer network, the complicated morphologies would be more common in the single-layer graphite structures. In this contribution, we report the observation and characterization of a new material of monolayer graphitic structure by electron diffraction, HREM, EELS.The synthesis process used in this study is reported early. We utilized a composite anode of graphite and copper for arc evaporation in helium.

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Characterization of short-term salinity fluctuations in the Neretva River Delta situated in the southern Adriatic Croatia using Landsat-5 TM

Ecological Indicators ◽

10.1016/j.ecolind.2019.105924 ◽

2020 ◽

Vol 110 ◽

pp. 105924 ◽

Cited By ~ 3

Author(s):

Ivan Racetin ◽

Andrija Krtalic ◽

Veljko Srzic ◽

Monika Zovko

Keyword(s):

River Delta ◽

Short Term ◽

Landsat 5 Tm

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Electrochemical Characterization of Single Layer Graphene/Electrolyte Interface: Effect of Solvent on the Interfacial Capacitance

Angewandte Chemie International Edition ◽

10.1002/anie.202104884 ◽

2021 ◽

Author(s):

Yih‐Chyng Wu ◽

Jianglin Ye ◽

Gengping Jiang ◽

Kun Ni ◽

Na Shu ◽

...

Keyword(s):

Single Layer ◽

Electrochemical Characterization ◽

Interface Effect ◽

Single Layer Graphene ◽

Effect Of Solvent ◽

Layer Graphene ◽

Electrolyte Interface ◽

Interfacial Capacitance

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Thermal decomposition of multilayer honeycomb core laminate sandwich composite panels in cone calorimeter apparatus – Effect of the top decomposed layer

Journal of Composite Materials ◽

10.1177/0021998321990873 ◽

2021 ◽

pp. 002199832199087

Author(s):

Hussain Najmi ◽

Jocelyn Luche ◽

Thomas Rogaume

Keyword(s):

Cone Calorimeter ◽

Single Layer ◽

Heat Fluxes ◽

Decomposition Process ◽

Phase Iii ◽

Sandwich Composite ◽

Back Surface ◽

Multilayer Composite ◽

In Fire

Multilayer composite materials are frequently used in aircraft interiors. Even though they have high properties (such as physical, chemical and mechanical properties), their application is limited due to lack of knowledge of their decomposition process and on the interaction between different layers in fire. In the present work, two types of composites with 3 and 4 layers are studied. The fire characterization of multilayer composite is studied in 3 different phases using ISO-5660 cone calorimeter at two heat fluxes (35 and 50 kW.m−2). Phase-I mainly concentrates on the decomposition of single layer materials (paint, laminate and honeycomb) while in phase-II and phase-III, different assemblies are formed using a single layer material and studied in the same experimental configuration. In all the three phases, back surface temperatures of the materials or assemblies are measured and analyzed with different gas productions which allow to understand the dynamics of the decomposition process. The finding from the cone calorimeter study suggests that the ignition primarily depends on the top layer behavior of the composite. The permeability analysis on the top layer of the composite confirms that decomposed layer of paint offers more resistance to the volatile gases escaping from the composite. At the end of the study, thermal conductivity is determined and the ignition temperature of both the composite is determined.

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Physical and Biological Characterization of Ferromagnetic Fiber Networks: Effect of Fibrin Deposition on Short-Term In Vitro Responses of Human Osteoblasts

Tissue Engineering Part A ◽

10.1089/ten.tea.2014.0211 ◽

2015 ◽

Vol 21 (3-4) ◽

pp. 463-474 ◽

Cited By ~ 8

Author(s):

Rose L. Spear ◽

Brajith Srigengan ◽

Suresh Neelakantan ◽

Wolfram Bosbach ◽

Roger A. Brooks ◽

...

Keyword(s):

Biological Characterization ◽

Fibrin Deposition ◽

Short Term ◽

Human Osteoblasts ◽

Fiber Networks

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The synthesis and characterization of a new family of single layer cuprates LnBaCuO2BO3 (Ln=La, Pr, Nd, Sm, Eu and Gd)

Physica C Superconductivity ◽

10.1016/0921-4534(93)90754-e ◽

1993 ◽

Vol 213 (1-2) ◽

pp. 26-32 ◽

Cited By ~ 17

Author(s):

Li Rukang ◽

R.K. Kremer ◽

J. Maier

Keyword(s):

Single Layer ◽

Synthesis And Characterization ◽

New Family

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Characterization of Glass-Ceramics by TEM

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.562-565.809 ◽

2013 ◽

Vol 562-565 ◽

pp. 809-812 ◽

Cited By ~ 1

Author(s):

Xiao Qing Liu ◽

Jun Lin Xie ◽

Feng He ◽

Hu Yang

Keyword(s):

Electron Beam ◽

Carbon Film ◽

Glass Ceramics ◽

Single Layer ◽

Double Layers ◽

Characterization Technique

The characterization technique of glass-ceramics by TEM was discussed by comparing the effects of single layer carbon film technique and double layers carbon film technique on the microstructure of Li-Al-Si glass-ceramics. The results show that double layers carbon film technique can improve glass-ceramics sample’s conductivity, reduce the induction of elctron beam on glass-ceramics, and avoid the temperature increasing of glass-ceramics particles caused by the charges aggregation on the particles’ surface when TEM electron beam hit down, prevent glass-ceramics from crystallization and the transformation of microstructurec. So, compared with single layer carbon film technique, double layers carbon film technique is more suitable for the research of microsture of glass-ceramics by TEM.

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