Nitrides
Mostrando 1-12 de 49 artigos, teses e dissertações.
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1. An Overview of the Photocatalytic H2 Evolution by Semiconductor-Based Materials for Nonspecialists
The solar-to-chemical energy conversion is promising to tackle sustainability challenges toward a global future. The production of H2 from sunlight represents an attractive alternative to the use of carboniferous fossil fuels to meet our energy demands. In this context, the water splitting reaction photocatalyzed by semiconductors that can be excited under v
J. Braz. Chem. Soc.. Publicado em: 2020-02
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2. Influence of the Gas Pressure of Plasma Nitriding on the Structural, Mechanical and Tribological Surface Properties of AISI 316L
In this paper, the influence of gas nitriding (80% H2-20% N2) pressure (between 3 and 7 Torr) on the modification of surface properties of AISI 316L stainless steel is examined. The structural, mechanical, tribological and electrochemical properties of the layer produced in disk samples were studied. The samples’ characteristics were determined by scanning
Mat. Res.. Publicado em: 15/07/2019
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3. Enhancement of Pitting Corrosion Resistance of Austenitic Stainless Steel Through Deposition of Amorphous/Nanocrystalline Oxy-nitrided Phases by Active Screen Plasma Treatment
In this research, AISI 304 austenitic stainless steels were efficient treatment using active screen plasma oxy-nitriding technique. The modified layers were characterized by X-ray photoelectron spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopes, and atomic force microscopy. In addition, the pitting corrosion resi
Mat. Res.. Publicado em: 29/10/2018
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4. Mass Spectrometry Study of Ammonia Formed During Plasma Nitrocarburizing and Nitriding Processes
In this work, we used mass spectrometry to investigate ammonia (NH3) formed during the nitrocarburizing and nitriding processes of α-Fe sintered and low alloy steel by using d.c. glow discharges in different N2/H2/CH4 gas concentration mixtures. Experiments were conducted using two different configurations: one to collect and analyze species probed primaril
Mat. Res.. Publicado em: 16/07/2018
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5. On the Effect of Aluminum on the Microstructure and Mechanical Properties of CrN Coatings deposited by HiPIMS
Hard coatings are a suitable solution for increasing the lifetime of tools and components employed in different industrial applications. Coatings of transition metal nitrides have great use for tribological applications due to due to their unique mechanical properties. Although widely employed, current deposition methods such as cathodic arc evaporation prod
Mat. Res.. Publicado em: 12/04/2018
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6. Corrosion Behavior of Plasma Nitrided and Nitrocarburised Supermartensitic Stainless Steel
Supermartensitic stainles steels (SMSS's) are a new generation of martensitic steels that have been increasingly used in oil and gas applications due to their adequate corrosion resistance and mechanical properties. In the present study, SMSS specimens (UNS S41425) were solution heat treated and air cooled followed by plasma nitriding and nitrocarburising at
Mat. Res.. Publicado em: 12/03/2018
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7. Influence of heat treatments on the microstructure and degree of sensitization of base metal and weld of AISI 430 stainless steel
ABSTRACT AISI 430 is a non-stabilized ferritic stainless steel grade with carbon content lower than 0.12%.After hot and cold rolling this material is annealed. The slow cooling after soaking at temperatures between 900oC and 1000oC promotes the formation of a high quantity of carbides and nitrides, while the rapid cooling partially suppresses the formation o
Matéria (Rio J.). Publicado em: 08/01/2018
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8. Characterization of the Austenite Reformation Mechanisms as a Function of the Initial Ferritic State in a UNS S32304 Duplex Stainless Steel
Aiming to better understand the effects of heat treatment parameters on Ferrite-Austenite phase transformation in a 2304 duplex stainless steel different thermal cycles were applied to this steel in a quenching dilatometer. The obtained microstructures were characterized by optical microscopy, transmission electron microscopy and electron backscatter diffrac
Mat. Res.. Publicado em: 17/08/2017
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9. Short-term Creep Properties and Fracture Surface of 18 Ni (300) Maraging Steel Plasma Nitrided
Plasma nitriding of a solution annealed and aged 300 grade maraging steel was studied aiming to increase the creep resistance. The surface microhardness reached 1,140 HV, producing 50 µm layer composed of ε-Fe3N and γ'-Fe4N nitrides at the uppermost sample layer. The inner core remained unaltered presenting typical plate-like martensite microstructure of
Mat. Res.. Publicado em: 13/03/2017
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10. Wear and Corrosion Study of Plasma Nitriding F53 Super duplex Stainless Steel
Super duplex stainless steels (SDSS) have high corrosion resistance because of their high contents of chromium, nickel, molybdenum and nitrogen but low wear resistance. To improve the wear resistance of these steels without affecting their corrosion resistance, samples of SDSS were treated by plasma ion nitriding at temperatures ranging from 350 °C to 570 �
Mat. Res.. Publicado em: 22/09/2016
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11. Plasma-spray synthesis and characterization of ti-based nitride and oxide nanogranules
The synthesis of nanosized Ti-based nanogranules via plasma spraying is reported. The synthesis route involved use of both nitrogen and oxygen gases with varying results. In the case of nitrogen, a mixture of titanium nitrides were produced, yielding both the Ti2N and the sub-stoichiometric TiN0.61 compounds. In the case of oxygen, both the stoichiometric ru
Mat. Res.. Publicado em: 15/08/2014
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12. Pulsed dc discharge in the presence of active screen for nitriding of high carbon steel
A discharge of nitrogen - hydrogen mixture by 50 Hz pulsed dc in the presence of active screen cage is investigated by optical emission spectroscopy (OES). The aim is to identify the parameters (mixture ratio, filling pressure and current density) that may lead to high concentration of active species (N2, N2+ and N). The maximum concentration in this experim
Mat. Res.. Publicado em: 22/07/2014