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Title: Enhancing Ductility of AL6061+ 10 wt.% B4C Through Equal-Channel Angular Extrusion Processing

Abstract

Additions of high modulus particles to aluminum alloys offer the potential developing a high stiffness, lightweight composite. Powder metallurgy was used to create a metal matrix composite of aluminum alloy, 6061, and 10 wt% boron carbide particles. Characterization of the as-fabricated material showed the presence of agglomerates of B4C particles and some residual porosity. Evaluation of the mechanical properties showed little improvement to the elastic modulus, low tensile strength and no significant amount of ductility. The material was ECAE processed using a variety of parameters, e.g. temperature, number of passes through the die, route, intermediate anneal, etc. Subsequent microstructural characterization revealed redistribution of the B4C particles. ECAE processing also eliminated residual porosity and improved the elastic modulus as well as other mechanical properties. The biggest improvement was observed in the elongation to fracture which increased to >10%.

Authors:
Publication Date:
Research Org.:
Idaho National Laboratory (INL)
Sponsoring Org.:
DOE - EE
OSTI Identifier:
912397
Report Number(s):
INEEL/JOU-04-02543
Journal ID: ISSN 0921-5093; TRN: US200801%%830
DOE Contract Number:
DE-AC07-99ID-13727
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Science and Engineering. A, Structural Materials: Properties, Microstructure and Processing; Journal Volume: 410-411
Country of Publication:
United States
Language:
English
Subject:
32 - ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION, 36 - MATERIALS SCIENCE, 42 - ENGINEERING; ALLOYS; ALUMINIUM; BORON CARBIDES; DUCTILITY; ELONGATION; EVALUATION; EXTRUSION; FLEXIBILITY; FRACTURES; MECHANICAL PROPERTIES; POROSITY; POWDER METALLURGY; PROCESSING; TENSILE PROPERTIES; 6061; boron carbide,; Equal Channel angular Extrusion; metal matrix composites

Citation Formats

Thomas M. Lillo. Enhancing Ductility of AL6061+ 10 wt.% B4C Through Equal-Channel Angular Extrusion Processing. United States: N. p., 2005. Web. doi:10.1016/j.msea.2005.08.093.
Thomas M. Lillo. Enhancing Ductility of AL6061+ 10 wt.% B4C Through Equal-Channel Angular Extrusion Processing. United States. doi:10.1016/j.msea.2005.08.093.
Thomas M. Lillo. Tue . "Enhancing Ductility of AL6061+ 10 wt.% B4C Through Equal-Channel Angular Extrusion Processing". United States. doi:10.1016/j.msea.2005.08.093.
@article{osti_912397,
title = {Enhancing Ductility of AL6061+ 10 wt.% B4C Through Equal-Channel Angular Extrusion Processing},
author = {Thomas M. Lillo},
abstractNote = {Additions of high modulus particles to aluminum alloys offer the potential developing a high stiffness, lightweight composite. Powder metallurgy was used to create a metal matrix composite of aluminum alloy, 6061, and 10 wt% boron carbide particles. Characterization of the as-fabricated material showed the presence of agglomerates of B4C particles and some residual porosity. Evaluation of the mechanical properties showed little improvement to the elastic modulus, low tensile strength and no significant amount of ductility. The material was ECAE processed using a variety of parameters, e.g. temperature, number of passes through the die, route, intermediate anneal, etc. Subsequent microstructural characterization revealed redistribution of the B4C particles. ECAE processing also eliminated residual porosity and improved the elastic modulus as well as other mechanical properties. The biggest improvement was observed in the elongation to fracture which increased to >10%.},
doi = {10.1016/j.msea.2005.08.093},
journal = {Materials Science and Engineering. A, Structural Materials: Properties, Microstructure and Processing},
number = ,
volume = 410-411,
place = {United States},
year = {Tue Nov 01 00:00:00 EST 2005},
month = {Tue Nov 01 00:00:00 EST 2005}
}
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