Grain Boundaries
Mostrando 1-12 de 87 artigos, teses e dissertações.
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1. Microstructure and diametral fracture strength of spark plasma sintered WC-6Co-0.2B and WC-6Co-0.5B ceramic composites from nanosized and metastable WC powders
Abstract The present work aimed at evaluating the microstructures and mechanical properties of spark plasma sintered WC-6 wt% Co ceramic composites doped with boron (0.2 and 0.5 wt%). W-50 at% C (W-6.13 wt% C) powders produced under different milling times (20, 60, 180, and 600 min) were used as starting materials and subsequently mixed with Co (6 wt%) and B
Cerâmica. Publicado em: 2022
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2. Phase Separation and Development of the Microstructure for Stainless Steel to Copper Alloy Weld Joints Using a Fiber Laser
ABSTRACT Stainless steel and copper alloys joints are often applied in aerospace, marine and power industries where both high thermal and electrical conductivity (Cu) and corrosion resistance (steel) are required. In the aerospace industry, in particular for the combustion chamber of rocket engines, copper and steel combinations offer perfect materials selec
J. Aerosp. Technol. Manag.. Publicado em: 10/10/2019
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3. Effect of Ca Content on Properties of Extruded Mg-3Zn-0.5Sr-xCa Alloys for Medical Applications
Mg-3Zn-0.5Sr-xCa(wt.%) (x=0, 0.2, 0.5) alloys were fabricated by casting and hot extrusion. X-ray diffraction (XRD) and optical microscopy observation showed that the microstructure of Mg-3Zn-0.5Sr-xCa alloys was composed of α-Mg matrix and Mg17Sr2 phase precipitated along grain boundaries. The tensile strength of the alloy increased from 255MPa to 305MPa w
Mat. Res.. Publicado em: 30/09/2019
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4. Influence of Zirconium Percentage on Microhardness and Corrosion Resistance of Ti50 Ni50-xZrx Shape Memory Alloys
To obtain high temperature shape memory alloys of the lower cost Ni-Ti-X system, elements such as Hf and Zr are introduced to modify the thermal and mechanical properties of these alloys. This work studied the production and characterization of Ti50 Ni50-x Zrx alloys (x = 0, 5, 10 at.%) with the aim of improving their thermal, mechanical and corrosion resist
Mat. Res.. Publicado em: 19/08/2019
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5. Fabrication of Fe-2.1 wt.% Si Alloy Sheets with Dominant Goss Texture Through Thickness
Macro- and micro-texture of Fe-2.1 wt.% Si alloy sheets were investigated and analyzed by X-ray diffraction and electron backscattered diffraction techniques. A Goss ({110}<001>) component accompanied by extremely weak γ (<111>//ND, normal direction) fiber is successfully formed through the sheet thickness after primary recrystallization and considerable gr
Mat. Res.. Publicado em: 15/07/2019
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6. Effects of composition on transformation temperatures and microstructure of Ni-Ti-Hf shape memory alloys
Abstract High transformation temperature shape-memory alloys (HTSMA) usually present a martensitic transformation temperature (Ms) starting at 100 ºC. That is the case of high nickel Ni-Ti-Hf alloys. This article presents experimental results obtained from arc melting of Ni50Ti50-XHfX .at% (X = 8, 11, 14, 17 and 20 .at%) alloys. This process homogenized eve
REM, Int. Eng. J.. Publicado em: 2019-06
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7. Avaliação da Adição de Ti, Nb e (Ti+Nb) na Microestrutura e Susceptibilidade à Sensitização de Aços Inoxidáveis Ferríticos Submetidos à Soldagem TIG
Resumo Neste estudo, a microestrutura e a resistência à corrosão intergranular de aços inoxidáveis ferríticos com adições de Nb, Ti e (Ti+Nb) submetidos à soldagem TIG foram investigadas. A caracterização estrutural dos cordões de solda foi realizada através de microscopias óptica (MO) e eletrônica de varredura (MEV) e espectroscopia por energ
Soldag. insp.. Publicado em: 16/05/2019
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8. EBSD Analysis of Orientation Gradients Developed near Grain Boundaries
The local misorientation and orientation gradient development near grain boundaries (GBs) are analyzed in a deep drawing quality steel sheet (AKDQ) subjected to interrupted tensile tests in a notched sample. The microstructure is studied using electron backscatter diffraction (EBSD) with subgrain-level spatial resolution. The evolution of misorientation accu
Mat. Res.. Publicado em: 10/01/2019
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9. The Contribution of Mechanical Spectroscopy to Understanding Grain Boundary Sliding
This review paper shows that grain boundary sliding (GBS) is a general phenomenon occurring in all classes of inorganic materials: ceramics, metals and composite materials. The occurrence of relaxations attributed to GBS is also quite general and therefore the mechanical spectroscopy constitutes a sensitive and universal technique to study such phenomenon. G
Mat. Res.. Publicado em: 25/10/2018
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10. Crecimiento de grano tridimensional con partículas móviles usando método de Monte Carlo
ABSTRACT In this paper we present a simulation model of grain growth with moving particles in three dimensions using the Monte Carlo method. The effect of concentration and particle size on grain size was studied. In general, it was possible to observe the migration of the particles towards the grain boundaries and the braking that they produce on the moveme
Matéria (Rio J.). Publicado em: 19/07/2018
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11. 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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12. Efecto del tratamiento térmico sobre la resistencia mecánica, corrosión intergranular y exfoliación de la aleación de aluminio 7075
ABSTRACT In this study, the effects of heat treatments in the peak aged (T6), overaged (T73) and retrogression and reaging (RRA, retrogression at 200 °C for 10 min) on the microstructure, mechanical strength, exfoliation corrosion and intergranular corrosion of aluminum alloy 7075, has been investigated by optical microscope, scanning electron microscopy, t
Matéria (Rio J.). Publicado em: 19/07/2018