Microalloyed Steels
Mostrando 13-22 de 22 artigos, teses e dissertações.
-
13. Grain size evolution of a vanadium microalloyed steel during bar rolling mill - 38MnSiV5. / Estudo da evolução do tamanho de grão na laminação a quente de barras de aço médio carbono microligado ao vanádio - 38MnSiV5.
Microalloyed steels are used as forging stock for many automotive parts such as crankshafts and connecting rods. Using mathematical equations describing the recrystallization kinetics and grain growth, a spreadsheet has been developed to simulate the austenitic grain size evolution during bar rolling mill schedules as a function of temperature, strain rate a
Publicado em: 2008
-
14. Estudo da transformação durante o resfriamento continuo e da microestrutura do aço microligado X80 utilizado na construção de tubos para transporte de gás natural e petróleo. / Study of the transformation during the continuous cooling and the microstructure of microalloyed steel X80 used in the building of pipelines for gas and oil transport.
The continuous increase of energy generated from petroleum and natural gas created the need to improve the mechanical properties of microalloyed steels used in gas and oil pipelines, in order to increase their flow with smaller costs and higher reliability. The control of the different phases, morphology of microconstituents like ferrite plus carbide aggrega
Publicado em: 2008
-
15. Investigação experimental do comportamento dúctil de aços API-X70 e aplicação de curvas de resistência J-∆a para previsão de colapso em dutos. / Experimental analysis of ductile behaviour of API-X70 steels and use of resistance J-∆a curves for predicting pressure collapse of pipelines.
This study presents the experimental investigation of the ductile behaviour of microalloyed pipeline steel. Additionally, it extends the computational cell methodology to model Mode I crack extension in a high strength low alloy HSLA steel. Laboratory testing of an API 5L X70 steel at room temperature using standard, deep crack C(T) specimens provides the cr
Publicado em: 2004
-
16. Estudo das transformações de fase de aços TRIP ao Si-Mn microligados com Nb. / Phase transformations study on Nb microalloyed Mn - Si TRIP steels.
The phase transformation kinetics of five Nb microalloyed Si-Mn TRIP steels was studied under continuous cooling and isothermal treatments, using dilatometric techniques, morphologic characterization, Thermocalc computational thermodynamics and Dictra numerical simulation. WDS and EDS X-ray microanalysis and Dictra numerical modeling of C, Mn and Si distribu
Publicado em: 2003
-
17. Influencia da taxa de resfriamento nas propriedades mecanicas e no micromecanismo de fratura de um aço microligado com niobio e titanio / The effect of cooling rate on the mechanical properties and fracture micromechanisms in a low carbon microalloyed niobium-titanium steel
In the last years the plain low-carbon steels have been replaced by the microalloyed steels in several applications as ship structure, pipeline, and several other applications in the automobile industry. Nowadays, a lot of effort has been pointed out to obtain steels with microstructures to improve the relationship between strength and ITacture toughness. Th
Publicado em: 1997
-
18. Avaliação dos micromecanismos de fratura de um aço microligado ao Ti e Nb em algumas condições microestruturais
The microalloyed steels are being utilized for substituting conventional structural steels and it leads to the necessity of improvement of its mechanical properties, mostly the strength/toughness relationship. It is known that these properties are related to the fracture micromechanisms when rupture occurs and this work s purpose is to characterize and anali
Publicado em: 1997
-
19. Propriedades mecanicas de um aço baixo carbono microligado com titanio e niobio em algumas condições microestruturais
The microalloyed steels have been utilized in several applications: one of these applications is the substitution of the conventional structural steels. As a result of that, it is necessary to improve the relationship between strength and fracture toughness by microstructural optimization, permiting weight saving design. The purpose of this work is to analyz
Publicado em: 1996
-
20. Caracterização da temperabilidade de um aço C-Mn microligado ao boro, através de dilatometria e curvas de transformações de fases por resfriamento contínuo. / C-Mn boron microalloyed steel hardenability characterization throught dilatometry and continuous cooling transformations curves.
No presente trabalho, foi realizado um estudo sobre a influência da adição do boro em um aço C-Mn, nas transformações de fases por resfriamento contínuo, através da técnica dilatométrica. Para este estudo, utilizou-se dois aços de composição química semelhante: o aço 10B22 com 30 ppm de boro e o aço sem boro é o E1522, equivalente. Foram tra
Publicado em: 1996
-
21. Aplicação de tratamento termomecanico a um aço bainitico microligado com niobio, titanio e boro
The influence of different conditions of controlled rolling and cooling was studied, simulating the industrial process of hot strip mill. This simulation aimed the investigation of microstructure formation and mechanical properties of a low carbon bainitic steel microalloyed with niobium, titanium and boron. In addition to the analysis of process parameters,
Publicado em: 1995
-
22. Efeitos da adição de niobio na estrutura e propriedades dos aços com medio e alto teor de carbono
Medium and high carbon steels containing microalloying additions of niobium have, in recent years, been used for the manufacture of forged components in the automotive industry, rails and high strength concrete reinforcing bars. However, optimization of the strength and toughness properties of these materials has largely been empirical. The present work was
Publicado em: 1983