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Title: Theory of Magnetic Heterostructures on the Nanometer Scale

Abstract

No abstract provided.

Authors:
 [1];  [1]
  1. Texas A&M Research Foundation, College Station, TX (United States)
Publication Date:
Research Org.:
Texas A & M Univ., College Station, TX (United States)
Sponsoring Org.:
USDOE Chicago Operations Office (CO)
OSTI Identifier:
1185257
Report Number(s):
DOE-Chicago 46278-1
DOE Contract Number:
FG02-06ER46278
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English

Citation Formats

Pokrovsky, Valery L, and Saslow, W. M.. Theory of Magnetic Heterostructures on the Nanometer Scale. United States: N. p., 2014. Web. doi:10.2172/1185257.
Pokrovsky, Valery L, & Saslow, W. M.. Theory of Magnetic Heterostructures on the Nanometer Scale. United States. doi:10.2172/1185257.
Pokrovsky, Valery L, and Saslow, W. M.. Sat . "Theory of Magnetic Heterostructures on the Nanometer Scale". United States. doi:10.2172/1185257. https://www.osti.gov/servlets/purl/1185257.
@article{osti_1185257,
title = {Theory of Magnetic Heterostructures on the Nanometer Scale},
author = {Pokrovsky, Valery L and Saslow, W. M.},
abstractNote = {No abstract provided.},
doi = {10.2172/1185257},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sat Jun 14 00:00:00 EDT 2014},
month = {Sat Jun 14 00:00:00 EDT 2014}
}

Technical Report:

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  • The authors have rapid-solidification-processed many stainless steels by gas atomization and achieved strength improvements of over 50% relative to conventionally-processed stainless steels with concomitant improvement in corrosion and oxidation behavior. These strength improvements are most pronounced after aging treatments when elevated concentrations of oxygen and vanadium are present in the stainless steel. An austenitic (FCC) stainless steel was prepared by gas atomization and consolidated by hot extrusion at 900 C. These specimens were heat treated for 1 hour at 1,000 C and aged at 600 C for 500 hours. The microstructure of each alloy composition was observed in TEM withmore » bright field imaging. After aging, most alloys showed the same precipitate morphology as before aging. An obvious change, however, was found only in the alloy with highest oxygen content. A high number density of 15 to 20 nm diameter precipitates was measured in this alloy. Moreover, with weak-beam dark field imaging, a very high number density of coherent, 6 to 10 nm diameter precipitates is observed throughout the matrix by Moire fringe contrast. An atom probe field ion microscopy (APFIM) investigation showed that FIM provides high contrast imaging the precipitates. In order to get a more global view of the structure, energy-filtered composition imaging on a LEO EM 912 was used to map the oxygen and nitrogen in carbon extraction replicas of the aged specimens. These images confirm that the 18 nm precipitates are oxides, however, it appears that the 8 nm precipitates are not extracted.« less
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