Embrittlement
Mostrando 1-12 de 39 artigos, teses e dissertações.
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1. Behaviors of Embrittlement and Softening in Heat Affected Zone of High Strength X90 Pipeline Steels
Abstract The embrittlement and softening behaviors in heat affected zone of X90 pipeline steel were studied, and the influence of weld thermal cycle on microstructure and mechanical properties were discussed by combining the effect of peak temperature on the phase transition point (Ar3). Results show that there are embrittlement and softening zones existed i
Soldag. insp.. Publicado em: 15/08/2019
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2. Nitretação a plasma da junta soldada do aço inoxidável super duplex SAF 2507
RESUMO Os aços inoxidáveis superduplex (AISD) apresentam em sua microestrutura as fases ferrita e austenita, de modo a conciliar boas propriedades mecânicas e de resistência à corrosão. Estes materiais possuem grande aplicação na indústria de extração de petróleo e na petroquímica. Quando estão sujeitos a estas aplicações, os dutos de AISD so
Matéria (Rio J.). Publicado em: 20/05/2019
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3. Tensile Armor Wires Submitted to Slow Strain Rate Tests in a Corrosive Environment and Cathodic Protection: a Comparison Between Two Different Microstructures
Tensile armor in flexible pipes consists of two or more layers of steel wires. Damage to the outer sheath may cause ingress of seawater in the annular space and thus corrosion of the armor wires. This work focused on the susceptibility of these wires to stress corrosion cracking (SCC) and hydrogen embrittlement (HE) using a slow strain rate test (SSRT) under
Mat. Res.. Publicado em: 06/05/2019
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4. Método innovador de ensayos de impacto en altas temperaturas aplicado en aceros al carbono
ABSTRACT In this paper, an innovative method of impact tests at high temperature on sub-size Charpy V notched specimens is applied. The innovation lies in the method of heating the specimen, which is performed in situ on a Charpy impact machine type by alternating electrical current through the specimen. The specimens are heated in a few seconds (v=32 ºC/s)
Matéria (Rio J.). Publicado em: 19/07/2018
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5. The Hydrogen Cold Work Peak in BCC Iron: Revisited, with First Principles Calculations and Implications for Hydrogen Embrittlement
We examine experimental and theoretical results on the cold-work (Snoek-Köster) peak in bcc Fe due to H using density functional theory (DFT). We reaffirm that Seeger’s interpretation of the H cold-work peak (Hcwp), involving motion of H with kinks on non-screw dislocations associated with the intrinsic-dislocation α peak, has experimental backing. Use o
Mat. Res.. Publicado em: 21/06/2018
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6. In Situ Synchrotron Radiation Measurements During Axial Strain In Hydrogen Cathodically Charged Duplex Stainless Steel SAF 2205
The objective of this work is the evaluation of hydrogen effects on the martensitic transformation and strain hardening in Duplex Stainless Steels (DSS) SAF 2205 (UNS S32205/S31803). DSS are two-phase alloys (austenite and ferrite), which are used for applications requiring high mechanical strength, in corrosive environments. Therefore, it is necessary a bet
Mat. Res.. Publicado em: 18/12/2017
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7. Characterization of Impact Toughness Properties of DIN39MnCrB6-2 Steel Grade
Boron added steels in quenched and tempered condition have been widely used in applications where good mechanical properties and low cost are required. In this study, impact resistance of DIN 39MnCrB6-2 steel grade was investigated due to its criticality in automotive components. Metastable phase diagrams were built to guide heat treatments. The influence he
Mat. Res.. Publicado em: 04/12/2017
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8. Embrittlement and Corrosion Decay of a Cast Duplex Stainless Steel
Duplex stainless steels (DSS) are Fe-Cr-Ni-Mo alloys, with low carbon content, which have a favorable combination of mechanical properties and corrosion resistance. These characteristics are mainly attributed to a dual phase and refined microstructure, typical of these alloys, consisting of similar amounts of ferrite and austenite. For this reason, DSS are w
Mat. Res.. Publicado em: 20/07/2017
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9. Influence of Hydrogenation on Residual Stresses of Pipeline Steel Welded Joints
Hydrogen embrittlement is a phenomenon that affects the performance of steel used for oil and gas pipelines. This paper presents a study of the effect of hydrogenation on the residual stresses of an API 5L X65 steel pipe. Residual stresses were analyzed by X-ray diffraction technique using the sin2Ψ method. The hydrogenation of base metal and welded joint s
Mat. Res.. Publicado em: 15/08/2016
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10. Relationship between microstructure and fracture types in a UNS S32205 duplex stainless steel
Duplex stainless steels are susceptible to the formation of sigma phase at high temperature which could potentially be responsible for catastrophic service failure of components. Thermal treatments were applied to duplex stainless steels in order to promote the precipitation of different fractions of sigma phase into a ferrite-austenite microstructure. Quant
Mat. Res.. Publicado em: 07/06/2013
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11. Caracterização da nova liga Fe-C-Mn-Si-Cr: fragilização da martensita revenida e curvas de revenimento. / A new Fe-C-Mn-Si-Cr alloy characterization: tempered martensite embrittlement and tempering curves.
O aço SAE/AISI 52100 é utilizado para a fabricação de rolamentos como também na fabricação de outras peças e dispositivos como cames de eixo comando de válvulas. Um dos problemas desta liga é a necessidade de revenimentos em temperaturas muito baixas para obtenção de alta dureza e para evitar o fenômeno da fragilização da martensita revenida (
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 07/03/2012
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12. Fragilização por hidrogênio nos aços AISI 4340 (AMS 6414K e AMS 6415S) temperados e revenidos / Hydrogen embrittlement in AISI 4340 steel (AMS 6414K and AMS 6415S) quenched and tempered
O fenômeno da fragilização por hidrogênio no aço AISI 4340 foi investigado devido ao fato do mesmo ser um aço baixa liga de alta resistência bastante suscetível a este fenômeno. A análise foi feita por meio do ensaio de tenacidade à fratura por flexão baseado na norma ASTM E 399 - 09. A matéria prima utilizada foi fabricada segundo dois diferent
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 23/02/2012