Isochronal annealing studies ofn-type6H-SiC with positron lifetime spectroscopy

Positron annihilation was performed to study the isochronal annealing of wrought (2024, 7075) and casting ( AlSi 11.35 Mg 0.23, AlSi 10.9 Mg 0.17 Sr 0.06) aluminum alloys in the temperature range from room temperature to 773 K after they had been deformed at room temperature with 25% deformation. Two annealing stages of microstructures were distinguished which were attributed to recovery in 2024, and AlSi 11.35 Mg 0.23, AlSi 10.9 Mg 0.17 Sr 0.06 due to point and dislocations respectively, and only one due to dislocations in 7075.

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Vacancies in electron irradiated 6H silicon carbide studied by positron annihilation spectroscopy

MRS Proceedings ◽

10.1557/proc-792-r3.19 ◽

2003 ◽

Vol 792 ◽

Author(s):

C. H. Lam ◽

C. C. Ling ◽

C. D. Beling ◽

S. Fung ◽

H. M. Weng ◽

...

Keyword(s):

Silicon Carbide ◽

Positron Annihilation ◽

Electron Irradiation ◽

Room Temperature ◽

Positron Lifetime ◽

Positron Annihilation Spectroscopy ◽

Isochronal Annealing ◽

Positron Lifetime Spectroscopy ◽

Irradiation Process ◽

Positron Lifetime Measurement

ABSTRACTPositron lifetime spectroscopy was employed to study the as-electron-irradiated (10 MeV, 1×1018 cm-2) n-type 6H silicon carbide sample in the measuring temperature range of 15 K to 294 K. Isochronal annealing studies were also performed up to the temperature of 1373 K by carrying out the room temperature positron lifetime measurement. Negatively charged carbon vacancies and VCVSi divacancy were identified as the major vacancy type defects induced by the electron irradiation process. The concentration of the VCVSi divacancy was found to decrease dramatically after the 1973 K annealing.

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An Investigation of Point Defects in NiAl Using Positron Annihilation Techniques

MRS Proceedings ◽

10.1557/proc-552-kk8.6.1 ◽

1998 ◽

Vol 552 ◽

Author(s):

Werner Puff ◽

Bernd Logar ◽

Adam G. Balogh

Keyword(s):

Positron Annihilation ◽

Point Defects ◽

Proton Irradiation ◽

Positron Lifetime ◽

Composition Range ◽

Isochronal Annealing ◽

Doppler Broadening ◽

Positron Lifetime Spectroscopy ◽

Induced Defects

ABSTRACTVacancy-like defects in NiAl in the composition range 47 at.-% < CNi < 53 at.-% are investigated by means of positron lifetime spectroscopy and Doppler-broadening measurements. The observed lifetimes in the annealed samples confirm that defects are quenched-in during the production of the samples. Isochronal annealing of samples quenched at 1600°C and after proton irradiation show that the induced defects are quite different.

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Effect of Nature Aging on Positron Lifetime Spectroscopy in Casting and Wrought Al-alloys

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.265.13 ◽

2007 ◽

Vol 265 ◽

pp. 13-18 ◽

Cited By ~ 2

Author(s):

M.A. Abdel-Rahman ◽

M. Abdel-Rahman ◽

N.A. Kamel ◽

M.S. Abdallah ◽

Emad A. Badawi

Keyword(s):

Aluminum Alloys ◽

Positron Annihilation ◽

Point Defects ◽

Positron Lifetime ◽

Natural Aging ◽

Al Alloys ◽

Isochronal Annealing ◽

Mean Lifetime ◽

Positron Lifetime Spectroscopy

Positron annihilation has been performed in order to study the isochronal annealing of wrought (2024, 7075) and cast (AlSi11.35Mg0.23, AlSi10.9Mg0.17Sr0.06) aluminum alloys, at temperatures ranging from RT to 773K, after having been deformed at RT to 25% deformation. Two annealing stages of the microstructures were distinguished, which were attributed to recovery in (2024, AlSi11.35Mg0.23, AlSi10.9Mg0.17Sr0.06) due to point defects and dislocations, respectively, and only one (due to dislocations) in (7075). Also, natural aging for up to more than 650 days was studied as a function of mean lifetime.

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Nanometer size pores in ionic liquid loaded silica gel characterized by positron lifetime spectroscopy

physica status solidi (a) ◽

10.1002/pssa.201532487 ◽

2015 ◽

Vol 213 (1) ◽

pp. 165-169 ◽

Cited By ~ 2

Author(s):

Christian Herold ◽

Hubert Ceeh ◽

Thomas Gigl ◽

Markus Reiner ◽

Marco Haumann ◽

...

Keyword(s):

Ionic Liquid ◽

Silica Gel ◽

Positron Lifetime ◽

Nanometer Size ◽

Positron Lifetime Spectroscopy

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Defects in electron irradiated GaP studied by positron lifetime spectroscopy

Applied Physics A ◽

10.1007/bf01538526 ◽

1995 ◽

Vol 60 (6) ◽

pp. 541-544 ◽

Cited By ~ 5

Author(s):

A. Polity ◽

Th. Abgarjan ◽

R. Krause-Rehberg

Keyword(s):

Positron Lifetime ◽

Positron Lifetime Spectroscopy

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Study of Compensation Defects and Electron Irradiation-Induced Defects in Undoped SI-InP by Positron Lifetime Spectroscopy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.607.134 ◽

2008 ◽

Vol 607 ◽

pp. 134-136

Author(s):

Y.J. Zhang ◽

Ai Hong Deng ◽

You Wen Zhao ◽

J. Yu ◽

X.X. Yu ◽

...

Keyword(s):

Electron Irradiation ◽

Positron Lifetime ◽

Deep Level ◽

High Concentration ◽

Positron Annihilation Lifetime ◽

Donor Type ◽

Positron Lifetime Spectroscopy ◽

Transient Spectroscopy ◽

Induced Defects ◽

Irradiation Induced Defects

Positron annihilation lifetime (PAL) spectroscopy，photo-induced current transient spectroscopy (PICTS) and thermally stimulated current (TSC) have been employed to study the formation of compensation defects and their evolvement under iron phosphide (IP) ambience or pure phosphide (PP) ambience. In the formation of IP SI-InP, the diffusion of Fe atoms suppresses the formation of some open-volume defects. As to PP SI-InP, VInH4 complexes dissociate into acceptor vacancies VInHn(n-3)(n=0,1,2,3), which compensate residual donor type defects and make the sample semi-insulating. Electron irradiation-induced deep level defects have been studied by TSC in PP and IP SI-InP, respectively. In contrast to a high concentration of irradiation-induced defects in as-grown and PP annealed InP, IP SI-InP has a very low concentration of defects.

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