Internal damping due to dislocation movements induced by thermal expansion mismatch between matrix and particles in metal matrix composites. [Al/SiC]

Journal Article · Sat May 01 00:00:00 EDT 1993 · Scripta Metallurgica et Materialia; (United States)

OSTI ID:6485033

Girand, C; Lormand, G; Fougeres, R; Vincent, A ^[1]

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1. GEMPPM, Villeurbanne (France)

In metal matrix composites (MMCs), the mechanical 1 of the reinforcement-matrix interface is an important parameter because it governs the load transfer from matrix to particles, from which the mechanical properties of these materials are derived. Therefore, it would be useful to set out an experimental method able to characterize the interface and the adjacent matrix behaviors. Thus, a study has been undertaken by means of internal damping (I.D.) measurements, which are well known to be very sensitive for studying irreversible displacements at the atomic scale. More especially, this investigation is based on the fact that, during cooling of MMC's, stress concentrations originating from differences in coefficients of thermal expansion (C.T.E.) of matrix and particles should induce dislocation movements in the matrix surrounding the reinforcement; that is, local microplastic strains occur. Therefore, during I.D. measurements vs temperature these movements should contribute to MMCs I.D. in a process similar to those involved around first order phase transitions in solids. The aim of this paper is to present, in the case of Al/SiC particulate composites, new developments of this approach that has previously led to promising results in the case of Al-Si alloys.

• OSTI ID: 6485033
• Journal Information: Scripta Metallurgica et Materialia; (United States), Vol. 28:9; ISSN 0956-716X
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
DAMPING
SILICON CARBIDES
COMPOSITE MATERIALS
DISLOCATIONS
EXPERIMENTAL DATA
INTERFACES
TEMPERATURE DEPENDENCE
THERMAL EXPANSION
THERMAL STRESSES
ALLOYS
CARBIDES
CARBON COMPOUNDS
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DATA
EXPANSION
INFORMATION
LINE DEFECTS
MATERIALS
NUMERICAL DATA
SILICON COMPOUNDS
STRESSES
360606* - Other Materials- Physical Properties- (1992-)