Martensite
Mostrando 25-36 de 136 artigos, teses e dissertações.
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25. Estudio del comportamiento en enfriamiento continuo del acero martensítico ferrítico de activación reducida F82H
ABSTRACT 9% Cr martensitic-ferritic steels are currently the privileged candidates to manufacture structural components of the so-called Generation IV nuclear fission reactors, because they exhibit very good thermophysical and mechanical properties under neutron irradiation. Along with them, the so-called Reduced Activation Ferritic-Martensitic steels (RAFM�
Matéria (Rio J.). Publicado em: 19/07/2018
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26. Optimización del proceso RSW para acero DP 1000
ABSTRACT In recent times new materials have been introduced in automobiles construction in order to reduce their weight and consequently fuel consumption and emissions level. Among them are Dual Phase (DP) steels, constituted by a ferritic matrix with martensite islands. Resistance Spot Welding (RSW) is the most commonly used welding process in the automotiv
Matéria (Rio J.). Publicado em: 19/07/2018
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27. Estudio de la microestructura de un cordón de soldadura de un acero P91 mediante microscopía electrónica de transmisión
ABSTRACT In the present work the microstructural characterization of a single-pass weld of 9Cr1MoVNb P91 steel performed by the flux-cored arc welding (FCAW) process in the “as welding” condition has been carried out by means of transmission electron microscopy. P91 steel offers a good weldability, but the mechanical properties of the welded joints are f
Matéria (Rio J.). Publicado em: 19/07/2018
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28. Impact of Alloy Composition and Thermal Stabilization on Martensitic Phase Transformation Structures in CuAlMn Shape Memory Alloys
Alloys of CuAlMn are known as cheap, high strength shape memory alloys with an excellent damping capacity within their austenitic-martensitic phase transformation, compared to alloy systems like NiTi, CuZnAl or MnCu. But CuAlMn alloys have disadvantage due to generation of voids by a high shrinkage which further increases the existing proneness to stress cra
Mat. Res.. Publicado em: 19/07/2018
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29. The Wire Drawing Mechanics of Near-Equiatomic NiTi SMA
The wire drawing mechanic of Ti-49.82Ni (at. %) Shape Memory Alloy (SMA) was investigated through the true stress-strain curves and drawing stresses. The tensile tested solution treated wire presented a four steps elongation at temperatures below the austenite finish temperature (AF), and a conventional one-step behavior above the martensite deformation temp
Mat. Res.. Publicado em: 26/03/2018
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30. 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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31. Effect of Austenitizing Temperature on Mechanical Properties of the Mixed Bainite - Martensite Microstructure in CrMoV Steel
The effect of austenitizing temperature on mechanical properties of the mixed bainite - martensite microstructure in CrMoV steel was studied in the present work. The result showed that at low austenitizing temperature (910°C - 1000°C), the mixed microstructures containing 12-28% volume fraction of lower bainite showed higher yield and tensile strength than
Mat. Res.. Publicado em: 27/11/2017
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32. Tempering Temperature Influence on 13Cr4Ni0.02C Steel Corrosion Resistance
The thermal treatments employed in alloys are essential to obtaining desired microstructures and corrosion resistance properties. In this paper the low carbon martensitic steel 13Cr4Ni0.2C with different tempering temperatures was studied using potentiodynamic polarization technique in synthetic marine environment, in order to evaluate the effect of the temp
Mat. Res.. Publicado em: 13/11/2017
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33. Fracture Modes of AISI Type 302 Stainless Steel Under Metastable Plastic Deformation
Martensitic transformation can be induced by plastic deformation in metastable iron-based alloys, such as stainless steels containing limited amounts of C, Ni and Cr. This transformation takes place at the temperature range from Ms and Md, usually at relatively lower temperature values. The transformed martensite has been associated with maximum ultimate str
Mat. Res.. Publicado em: 09/11/2017
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34. Recovery Mechanisms in a Compressed Ni-Ti Superelastic Alloy
The present work studied the influence of annealing on a Ni-Ti alloy submitted to uniaxial compression. The stress-strain curve under compression showed the absence of the Stress-Induced-Martensite (SIM) plateau and 42% of remaining austenitic phase (B2). identified by the Electron Backscattered Diffraction (EBSD) technique on a Scanning Electronic Microscop
Mat. Res.. Publicado em: 19/10/2017
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35. Martensitic Transformation Under Compression of a Plasma Processed Polycrystalline Shape Memory CuAlNi Alloy
Shape memory alloys (SMA) are attracting considerable attention owing to possible applications from biomedical to aerospace. In particular, CuAlNi alloys present significant advantages associated with low cost, easy processing and superior thermo-electric conductivity over other SMAs such as the NiTi alloys. Characterization of some properties and structural
Mat. Res.. Publicado em: 31/08/2017
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36. Martensite Transformation Intergrain and Intragrain Autocatalysis in Fe-Ni alloys
This work presents a consolidated view of the autocatalysis, thermal and entropic effects in martensitic transformation of polycrystalline Fe-31wt%Ni-0.02wt%C, which has been a standard material for the investigation of fundamental aspects of the martensite transformation. The present work is based on the description of classical microstructure descriptors o
Mat. Res.. Publicado em: 24/08/2017