Iron Nitrides
Mostrando 1-9 de 9 artigos, teses e dissertações.
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1. 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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2. 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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3. 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
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4. Efeito do \ shot peening\ sobre a nitretação de peças de ferro produzidas por metalurgia do pó / The effect of shot peening on the gas nitriding of iron components produced by powder metallurgy
Atualmente, quando se tem a necessidade de nitretar peças produzidas pela metalurgia do pó, usa-se a nitretação a plasma. Apesar de ser um processo de alto custo, com diversas dificuldades operacionais e de ajuste de processo, a nitretação a plasma é o único processo viável para nitretar esses materiais por ter uma ação apenas superficial, não ap
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 02/07/2009
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5. Synthesis of nanostructured boron nitride and its potentially for application in cosmetology / Sínteses e caracterização de nitreto de boro nanoestrutrado com potencialidade de aplicação em cosmetologia
Regular use of appropriate cosmetics is an important resource for the maintenance of the skin health and, consequently, its beauty. The effect of ultraviolet rays is harmful to the health of the skin and can result in increase of the cancer incidence, aging and other undesirable cutaneous changes. The effects of the infra-red rays are less described in the s
Publicado em: 2009
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6. Efeito do carbono no processo de nitrocarburização com plasma pulsado da liga metalica AISI H13 / Carbon effect on pulsed plasma nitrocarburizing process in AISI H13 tool steel
This work presents a study on the effect of the incorporation of carbon and nitrogen on he formation of a singlephase homogeneous layer, composed by e -Fe2-3(C,N) carbonitrides, on the top surface of a AISI H13 tool steel. We also present studies on the effect of the incorporation of these elements (C and N) in the microstructure and in the mechanical and ch
Publicado em: 2007
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7. Surface treatments of a iron aloy by nitrogen ions / Tratamentos de superficies de uma liga ferrosa por ions de nitrogenio
The objective of this project is to study processes of plasma surface treatment with special emphasis to the differences these techniques might show in relation to others, looking forward to understand the process from surface phenomena. Two kinds of surface treatment have been studied, including three different techniques: ion beam nitriding, pulsed plasma
Publicado em: 2006
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8. Superficial Nitrogen Enrichment of Austenitic stainless steel ISO 5832-1 / ElevaÃÃo do teor superficial de nitrogÃnio no aÃo inoxidÃvel austenÃtico ISO 5832-1
The insertion of nitrogen in stainless steel has been studied since 1925. When in solid solution it produces a few effects such as: increase in mechanical strength, hardness, resistance to fatigue, to wear and corrosion. Although benefic effects of nitrogen on the proprieties of steel are well known, the introduction of this element in high amounts is not tr
Publicado em: 2001
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9. High-pressure highly reduced nitrides and oxides from chromitite of a Tibetan ophiolite
The deepest rocks known from within Earth are fragments of normal mantle (≈400 km) and metamorphosed sediments (≈350 km), both found exhumed in continental collision terranes. Here, we report fragments of a highly reduced deep mantle environment from at least 300 km, perhaps very much more, extracted from chromite of a Tibetan ophiolite. The sample consi
National Academy of Sciences.