Structure and deformation of continuous alumina fiber reinforced aluminum composites

Thesis/Dissertation · Tue Jan 01 04:00:00 EST 1991

OSTI ID:7039475

Isaacs, J A

Plastic deformation under uniaxial tension and compression of high purity aluminum reinforced with a high volume fraction of parallel alumina fibers is investigated. This material is chosen because there are no fiber/matrix chemical reactions for this system, and the only significant intrinsic hardening mechanism of the matrix is work hardening. The matrix substructure is characterized in the as-cast condition and after deformation by examination of electrolytically polished thin foils using transmission electron microscopy. Simple models to account for dislocation generation due to thermal stresses at smooth fibers on cooling the composite from processing temperatures, predict much lower dislocation densities than observed in the as-cast composite. A constant rate of work hardening is observed in tensile loading stage 2 for the composite, which is attributable to the fiber contribution, with little additional work hardening by the aluminum matrix. The reactivity of zirconia-alumina fibers with aluminum during high-temperature processing is also studied. It is determined that the ZrAl{sub 3} forms in the matrix by reaction between the fiber and the matrix at temperatures above 640C.

• Research Organization: Massachusetts Inst. of Tech., Cambridge, MA (United States)
• OSTI ID: 7039475
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360602* -- Other Materials-- Structure & Phase Studies
360603 -- Materials-- Properties
ALUMINIUM COMPOUNDS
ALUMINIUM OXIDES
CHALCOGENIDES
COMPOSITE MATERIALS
CRYSTAL STRUCTURE
DEFORMATION
FIBERS
MATERIALS
MICROSTRUCTURE
OXIDES
OXYGEN COMPOUNDS
REINFORCED MATERIALS
TEMPERATURE RANGE
TEMPERATURE RANGE 0400-1000 K
TRANSITION ELEMENT COMPOUNDS
ZIRCONIUM COMPOUNDS
ZIRCONIUM OXIDES