Shape Memory Effect
Mostrando 1-12 de 33 artigos, teses e dissertações.
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1. The Von Restorff effect in the Brazilian version of the Rey Auditory Verbal Learning Test in an elderly population
RESUMO. Efeito de von Restorff (efeito de isolamento) refere-se ao estímulo que é mais facilmente lembrado em relação a outros em tarefas de memória. Tal efeito foi demonstrado em diferentes faixas etárias com diferentes metodologias. Objetivo: Investigar: a) presença do efeito de isolamento numa população idosa avaliada com a nova versão brasilei
Dement. neuropsychol.. Publicado em: 2019-03
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2. The Influence of Microstructure and Mechanical Resistance on the Shape Memory of Ecae Processed Stainless Fe-Mn-Si-Cr-Ni-Co Steel
In the current work, XRD, SEM, EBSD and TEM techniques were used to evaluate the microstructure of stainless Fe-Mn-Si-Cr-Ni-Co shape memory steel processed by ECAE and annealed for one hour at temperatures ranging from 650ºC to 950ºC. The results were then correlated with the mechanical and shape-memory properties of the steel. It was observed that the sam
Mat. Res.. Publicado em: 09/08/2018
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3. Releasing systems for aerospace industry based upon Shape Memory Alloys: characterization of materials for actuators
ABSTRACT Releasing and deployment maneuvers carried out during space satellites launching are usually performed by utilizing pyrotechnics loads. However, it is considered convenient to replace this technique by others not requiring explosives (Non Explosive Actuators-NEA). This is mainly due to the necessity of reducing high-shock and vibrations induced leve
Matéria (Rio J.). Publicado em: 19/07/2018
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4. 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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5. Analysis of Compositional Modification of Commercial Aluminum Bronzes to Obtain Functional Shape Memory Properties
In copper-based shape memory alloys (SMAs), some exceptional phenomena, such as the shape memory effect (SME) or superelasticity (SE), are observable. However, commercial aluminum bronzes, Cu3Al-based alloys, do not present these functional properties (SME and/or SE) in their original state. Thus, since one of the main copper-based SMA systems is the Cu-Al-N
Mat. Res.. Publicado em: 17/08/2017
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6. Effect of Spun Velocities and Composition on the Microstructure and Transformation Temperatures of TiNi Shape Memory Ribbons
Ti‒50.13Ni and Ti‒49.62Ni (at.%) shape memory alloy ribbons were fabricated by melt-spinning method at different circumferential wheel velocities. The effects of wheel velocity, chemical composition and heat treatments on microstructure and Transformation temperature were investigated. Differences in wheel velocity led to differences in cooling rate and
Mat. Res.. Publicado em: 12/09/2016
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7. Effect of Spun Velocities and Composition on the R‒phase and Thermomechanical Behavior in Ti‒Ni Ribbons Electrically Heated
This work deals with structural, electrical and mechanical characterization of Ti‒50.13Ni and Ti‒49.62Ni (at.%) shape memory alloys (SMAs) fabricated at different circumferential wheel velocities. The effect of wheel velocity, chemical composition and heat treatments are investigated. The characterization of crystallographic phases of the Ti‒Ni ribbons
Mat. Res.. Publicado em: 08/04/2016
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8. Construction of a Morphing Wing Rib Actuated by a NiTi Wire
ABSTRACT: The main goal of this paper is to analyze if it is feasible to employ a trained shape memory alloy wire as a linear actuator to modify the camber of a morphing wing rib. In order to achieve this purpose, a morphing rib with a compliant trailing edge was proposed, developed, and subjected to structural analyses to ensure its flexibility. After the r
J. Aerosp. Technol. Manag.. Publicado em: 2015-12
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9. Mechanical Performance of Nickel-titanium Archwires
The purpose of the present work is to compare the mechanical properties of commercially available NiTi orthodontic archwires lots. Superelastic (SE) and heat-activated (HA) NiTi archwires from two lots of six manufacturers (3M, GAC, Tp, Orthosource, Orthometric and Morelli) were partitioned into eleven groups (n=132) and tested under three-point bending test
Mat. Res.. Publicado em: 03/11/2015
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10. Oxide Formation on NiTi Surface: Influence of the Heat Treatment Time to Achieve the Shape Memory
AbstractSeveral studies regarding superficial treatments of Nitinol (NiTi) shape-memory have been developed aiming to the improve corrosion resistance and to block the Ni release to adjacent tissues. The necessary heat treatment to achieve the shape memory effect normally occurs at temperatures between 500 and 600 °C. However, titanium oxide (TiO2) is forme
Mat. Res.. Publicado em: 2015-10
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11. Changes in the properties of Cu-Al-Mn shape memory alloy due to quaternary addition of different elements
Advantages of Cu based shape memory alloy include amongst other features, high transformation temperature, low cost of production, ease in manufacturing processes and ability to vary the achieved properties through alloying additions. It has been often reported that these alloys are very sensitive to the alloying additions in terms of properties achieved and
Matéria (Rio J.). Publicado em: 2015-03
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12. Microstructural evaluation on shape recovery in stainless Fe-Mn-Si-Cr-Ni-Co SMA processed by wire drawing
The effect of the microstructure on the shape recovery in stainless Fe-8Mn-5Si-13Cr-6Ni-12Co shape memory steel (SSMS) was evaluated using tensile tests and reversion temperature of 600ºC for a pre-strain of 4%. The tests were performed for a solution treated and annealed conditions at different temperatures after wire drawing of 57% area reduction. The bes
Mat. Res.. Publicado em: 30/05/2014