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Title: Growth of Co precipitates in irradiated dilute Ag-Co alloys

Abstract

The growth of Co precipitates in dilute AgCo alloys under 1.8 MeV Kr ion irradiation was investigated by a combination of x-ray diffraction and magnetic measurements. For alloys with Co compositions ranging from 8 to 20 at. % precipitates grow in volume approximately linearly with dose, with no indication of saturation. The variation of temperature from liquid nitrogen temperature to 300 deg. C had little effect on the growth behavior. Precipitation kinetics in these alloys is very different from that in dilute CuCo alloys, which showed steady state precipitate sizes at temperatures below 350 deg. C. We attribute the different behavior to the low solubility of Co in liquid Ag (in contrast to its complete solubility in liquid Cu). The quantitative results suggest that the growth of Co precipitates is derived from particle aggregation rather than Ostwald ripening.

Authors:
; ;  [1]
  1. Department of Materials Science and Engineering, Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)
Publication Date:
OSTI Identifier:
20884976
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 1; Other Information: DOI: 10.1063/1.2404780; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; AGGLOMERATION; COBALT; COBALT ALLOYS; CRYSTAL GROWTH; ION BEAMS; IRRADIATION; KRYPTON IONS; MEV RANGE 01-10; NITROGEN; PARTICLES; PRECIPITATION; SILVER ALLOYS; SOLUBILITY; STEADY-STATE CONDITIONS; X-RAY DIFFRACTION

Citation Formats

Chee, S. W., Krasnochtchekov, P., and Averback, R. S.. Growth of Co precipitates in irradiated dilute Ag-Co alloys. United States: N. p., 2007. Web. doi:10.1063/1.2404780.
Chee, S. W., Krasnochtchekov, P., & Averback, R. S.. Growth of Co precipitates in irradiated dilute Ag-Co alloys. United States. doi:10.1063/1.2404780.
Chee, S. W., Krasnochtchekov, P., and Averback, R. S.. Mon . "Growth of Co precipitates in irradiated dilute Ag-Co alloys". United States. doi:10.1063/1.2404780.
@article{osti_20884976,
title = {Growth of Co precipitates in irradiated dilute Ag-Co alloys},
author = {Chee, S. W. and Krasnochtchekov, P. and Averback, R. S.},
abstractNote = {The growth of Co precipitates in dilute AgCo alloys under 1.8 MeV Kr ion irradiation was investigated by a combination of x-ray diffraction and magnetic measurements. For alloys with Co compositions ranging from 8 to 20 at. % precipitates grow in volume approximately linearly with dose, with no indication of saturation. The variation of temperature from liquid nitrogen temperature to 300 deg. C had little effect on the growth behavior. Precipitation kinetics in these alloys is very different from that in dilute CuCo alloys, which showed steady state precipitate sizes at temperatures below 350 deg. C. We attribute the different behavior to the low solubility of Co in liquid Ag (in contrast to its complete solubility in liquid Cu). The quantitative results suggest that the growth of Co precipitates is derived from particle aggregation rather than Ostwald ripening.},
doi = {10.1063/1.2404780},
journal = {Journal of Applied Physics},
number = 1,
volume = 101,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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