Positron annihilation lifetime spectroscopy study of roller burnished magnesium alloy

Abstract The effect of roller burnishing on Vickers’ hardness and positron lifetimes in the AZ91HP magnesium alloy was studied. The microhardness increases with an increase in the burnishing force and with a decrease in the feed. The comparison of various methods of analysis of positron annihilation lifetime (PAL) spectra allowed identification of two components, which are related to solute-vacancy complexes and vacancy clusters, respectively. It was found that the increase in microhardness was related to the increase in the concentration of vacancy clusters.

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Positron Annihilation Lifetime Spectroscopy Study of the Formation of Mesoporous Materials from the Zeolite Precursor

Acta Physica Polonica A ◽

10.12693/aphyspola.125.775 ◽

2014 ◽

Vol 125 (3) ◽

pp. 775-777 ◽

Cited By ~ 2

Author(s):

S. Bosnar ◽

D. Bosnar ◽

B. Gržeta

Keyword(s):

Positron Annihilation ◽

Mesoporous Materials ◽

Positron Annihilation Lifetime Spectroscopy ◽

Spectroscopy Study ◽

Positron Annihilation Lifetime

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Positron annihilation lifetime spectroscopy study on epoxy moisture absorption

Journal of Physics Conference Series ◽

10.1088/1742-6596/443/1/012055 ◽

2013 ◽

Vol 443 ◽

pp. 012055 ◽

Cited By ~ 1

Author(s):

P M Gordo ◽

J M M Luis ◽

M F Ferreira Marques ◽

M Duarte Naia ◽

J J M Morais

Keyword(s):

Positron Annihilation ◽

Moisture Absorption ◽

Positron Annihilation Lifetime Spectroscopy ◽

Spectroscopy Study ◽

Positron Annihilation Lifetime

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Neutron Damage in Reactor Pressure-Vessel Steel Examined with Positron Annihilation Lifetime Spectroscopy

MRS Proceedings ◽

10.1557/proc-439-483 ◽

1996 ◽

Vol 439 ◽

Cited By ~ 2

Author(s):

Stephen E. Cumblidge ◽

Arthur T. Motta ◽

Gary L. Catchen

Keyword(s):

Positron Annihilation ◽

Pressure Vessel ◽

Reactor Pressure Vessel ◽

Positron Annihilation Lifetime Spectroscopy ◽

Pressure Vessel Steel ◽

Vessel Steel ◽

Positron Annihilation Lifetime ◽

Neutron Damage ◽

Positron Lifetimes ◽

Reactor Pressure

AbstractWe have used positron annihilation lifetime spectroscopy to study the development of damage and annealing behavior of neutron-irradiated reactor pressure-vessel steels. We irradiated samples of ASTM A508 nuclear reactor pressure-vessel steel to fast neutron 172 fluences of up to 1017 n/cm2, and we examined these samples using positron annihilation lifetime spectroscopy (PALS) to study the effects of neutron damage in the steels on positron lifetimes. Non-irradiated samples show two positron lifetimes: a 110 ps component corresponding to annihilations in the bulk material, and a 165 ps lifetime corresponding to annihilations in dislocation defects. The irradiated samples show an additional lifetime component of 300 ps in the PAL spectra and an increase in the proportion of annihilations with a 165 ps lifetime, suggesting that vacancies and vacancy clusters are present in the material after room temperature irradiation. The samples were then annealed to temperatures ranging from 210° C to 450° C. The positron lifetimes introduced by neutron damage disappear after annealing the samples at 280° C.

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