Anelastic Relaxation
Mostrando 1-12 de 13 artigos, teses e dissertações.
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1. Hysteretic Behavior of Twin Boundary Peak Due to Precipitation in Co-Ni-Cr alloy
Anelastic behavior and microstructural changes of a Co-Ni-Cr super-alloy were monitored over the temperature range 250-950ºC, by using several complementary techniques. Two grades of this alloy were used, differing by the presence of small quantity of beryllium (<1.5% at.). Thermoelectric power reveals two distinct precipitation stages. The first precipitat
Mat. Res.. Publicado em: 02/07/2018
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2. Relaxational Dynamics in the PYR14-IM14 Ionic Liquid by Mechanical Spectroscopy
The anelastic spectrum of the N-butyl-N-methyl-pyrrolidinium (trifluoromethanesulfonyl) (nonafluorobutanesulfonyl)imide (PYR14-IM14) is reported for the first time. On cooling, at 4 Kmin-1 the sample undergoes a glass transition around 190 K. In the liquid phase, a thermally activated relaxation process is measured and it is analyzed by means of a modified
Mat. Res.. Publicado em: 04/06/2018
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3. Mechanical Spectroscopy of Ti-15Zr-based Alloys with Mo Addition
In this paper, the effect of substitutional Mo amounts in internal friction and interstitial diffusion mechanisms was analyzed in Ti-15Zr-based alloys. Mechanical spectroscopy was obtained from room temperature up to 730 K with frequencies between 1 Hz and 40 Hz. Internal friction spectra were composed by anelastic relaxation peaks in β-type alloys (metasta
Mat. Res.. Publicado em: 27/11/2017
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4. Mechanical spectroscopy study of the Cu36Zr59Al5 and Cu54Zr40Al6 amorphous alloys
A mechanical spectroscopy study of Cu-Zr-Al bulk metallic glasses, was performed with two types of equipment: a Kê-type inverted torsion pendulum and an acoustic elastometer, working in the frequency ranges of Hz and kHz, respectively, with a heating rate of 1 K/min. The analysis of the anelastic relaxation shows similar spectra for both types of equipment
Mat. Res.. Publicado em: 23/10/2012
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5. Dynamical Elastic Moduli of the Ti-13Nb-13Zr biomaterial alloy by mechanical spectroscopy
Dynamical Elastic Moduli of the Ti-13Nb-13Zr biomaterial alloy were obtained using the mechanical spectroscopy technique. The sample with heat treatment at 1170K for 30 minutes and water quenched with subsequent aging treatment at 670 K for 3 hours (TNZ + WQ + 670 K/3 h), was characterized through decay of free oscillations of the sample in the flexural vibr
Mat. Res.. Publicado em: 04/09/2012
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6. Caracterização do módulo elástico por espectroscopia mecânica da liga Ti-13Nb-13Zr
In the present time the titanium and their alloys are begin widely studied in the field of biomaterials because of its suitable mechanical properties such as low elastic modulus, excellent corrosion resistance and high biocompatibility. Recent studies are being focused on alloys free of toxic elements as Al and V, which are contained in the alloy Ti-6Al-4V t
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 11/09/2011
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7. Glass transition and degree of conversion of a light-cured orthodontic composite
OBJECTIVE: This study evaluated the glass transition temperature (Tg) and degree of conversion (DC) of a light-cured (Fill Magic) versus a chemically cured (Concise) orthodontic composite. MATERIAL AND METHODS: Anelastic relaxation spectroscopy was used for the first time to determine the Tg of a dental composite, while the DC was evaluated by infrared spect
Journal of Applied Oral Science. Publicado em: 2009-12
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8. Determination of the oxygen and nitrogen interstitial diffusion coeficient in niobium by mechanical spectroscopy
Mechanical spectroscopy measurements have been extensively used in the last decades to obtain information about many aspects of the behavior of solutes in metallic materials. Metals of body-centered cubic lattice that contain heavy interstitial elements (oxygen, nitrogen and carbon) in solid solution, present anelastic relaxation peaks when submitted to cycl
Materials Research. Publicado em: 2006-12
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9. Measurement of oxygen atom diffusion in Nb and Ta by anelastic spectroscopy
Impurity interstitial atoms present in metals with BCC structure can diffuse in the metallic matrix by jumps to energetically equivalent crystallographic sites. Anelastic spectroscopy (internal friction) is based on the measurement of mechanical loss or internal friction as a function of temperature. Due to its selective and nondestructive nature, anelastic
Materials Research. Publicado em: 2005-09
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10. Activation Energy Measurement of Oxygen Ordering in a Nb-Ti Alloy by Anelastic Relaxation
Metals with bcc structure are able to dissolve large amounts of interstitial element atoms in the form of oxygen. These atoms diffuse through the lattice by jumping into octahedral sites with equivalent symmetry, causing strong alterations in the anelastic behavior. This paper reports on a study of Snoek relaxation in Nb-Ti alloys with oxygen in solid soluti
Materials Research. Publicado em: 2002-06
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11. Diffusion and anelastic relaxation due to hydrogen in solid solution in Nb-Ti and Nb-Zr alloys. / Difusão e relaxação anelástica devido ao hidrogênio em solução sólida em ligas de Nb-Ti e Nb-Zr.
We study the effect of hydrogen dissolved interstitially in niobium-titanium and niobium-zirconium alloys. In the niobimn-titanium alloys, the logarithmic decrement was studied by internal friction measurements in a torsion pendulum with frequency about 4.0 Hz, on pure and hydrogen doped samples. Our results showed the interaction of hydrogen with the metall
Publicado em: 1993
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12. Anisotropias induzidas em ligas ferromagnéticas amorfas / Induced anisotropy in amorphous ferromagnetic alloys
In this thesis we will present a series of studies related to induced magnetic anisotropies (Kind) in amorphous alloys. In order to get a more general view of this theme, we used several different kinds of annealings. The theoretical analysis of the data of Kind and magnetic after-effect (MAE) was performed using a model based on two-level systems (TLS). Fro
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 07/03/1991