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Title: Boron strengthening in FeAl

Abstract

The effect of boron on the strength of B2-structured FeAl is considered as a function of composition, grain size and temperature. Boron does not affect the concentrations of antisite atoms or vacancies present, with the former increasing and the latter decreasing with increasing deviation from the stoichiometric composition. When vacancies are absent, the strength increase per at. % B per unit lattice strain, {Delta}{sigma}/({Delta}c x {epsilon}) increases with increasing aluminum concentration, but when vacancies are present (>45 at. % Al), {Delta}{sigma}/({Delta}c x {epsilon}) decreases again. Boron increases grain size strengthening in FeAl. B strengthening is roughly independent of temperature up to the yield strength peak but above the point, when diffusion-assisted deformation occurs, boron strengthening increases dramatically.

Authors:
; ; ; ;  [1]; ;  [2]
  1. Dartmouth Coll., Hanover, NH (United States). Thayer School of Engineering
  2. Oak Ridge National Lab., TN (United States). Metals and Ceramics Div.
Publication Date:
Research Org.:
Oak Ridge National Lab., Metals and Ceramics Div., TN (United States)
Sponsoring Org.:
USDOE Office of Energy Research, Washington, DC (United States)
OSTI Identifier:
676870
Report Number(s):
ORNL/CP-98993; CONF-981054-
ON: DE99000376; BR: KC0201050;KC0201010; TRN: AHC29821%%3
DOE Contract Number:
AC05-96OR22464
Resource Type:
Technical Report
Resource Relation:
Conference: 1998 Minerals, Metals and Materials Society (TMS) fall meeting, Rosemont, IL (United States), 11-15 Oct 1998; Other Information: PBD: [1998]
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; MICROSTRUCTURE; YIELD STRENGTH; IRON ALLOYS; ALUMINIUM ALLOYS; INTERMETALLIC COMPOUNDS; BORON ADDITIONS; METALLURGICAL EFFECTS; LATTICE PARAMETERS; CHEMICAL COMPOSITION; EXPERIMENTAL DATA

Citation Formats

Baker, I., Li, X., Xiao, H., Klein, O., Nelson, C., Carleton, R.L., and George, E.P. Boron strengthening in FeAl. United States: N. p., 1998. Web. doi:10.2172/676870.
Baker, I., Li, X., Xiao, H., Klein, O., Nelson, C., Carleton, R.L., & George, E.P. Boron strengthening in FeAl. United States. doi:10.2172/676870.
Baker, I., Li, X., Xiao, H., Klein, O., Nelson, C., Carleton, R.L., and George, E.P. Sun . "Boron strengthening in FeAl". United States. doi:10.2172/676870. https://www.osti.gov/servlets/purl/676870.
@article{osti_676870,
title = {Boron strengthening in FeAl},
author = {Baker, I. and Li, X. and Xiao, H. and Klein, O. and Nelson, C. and Carleton, R.L. and George, E.P.},
abstractNote = {The effect of boron on the strength of B2-structured FeAl is considered as a function of composition, grain size and temperature. Boron does not affect the concentrations of antisite atoms or vacancies present, with the former increasing and the latter decreasing with increasing deviation from the stoichiometric composition. When vacancies are absent, the strength increase per at. % B per unit lattice strain, {Delta}{sigma}/({Delta}c x {epsilon}) increases with increasing aluminum concentration, but when vacancies are present (>45 at. % Al), {Delta}{sigma}/({Delta}c x {epsilon}) decreases again. Boron increases grain size strengthening in FeAl. B strengthening is roughly independent of temperature up to the yield strength peak but above the point, when diffusion-assisted deformation occurs, boron strengthening increases dramatically.},
doi = {10.2172/676870},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Sun Nov 01 00:00:00 EST 1998},
month = {Sun Nov 01 00:00:00 EST 1998}
}

Technical Report:

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