Damping mechanisms in 6061 Al/SiC/Gr hybrid metal matrix composites processed using spray deposition

Book · Sat Dec 31 04:00:00 EST 1994

OSTI ID:62980

Zhang, J; Perez, R J; Lavernia, E J ^[1]

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1. Univ. of California, Irvine, CA (United States)

Previous studies revealed that damping capacity of Al alloys can be improved through particle reinforced metal matrix composite (MMC) processing. Addition of graphite particles may produce a substantial increase in damping capacity but introduce a decrease in modulus. Addition of SiC particles, however, improves modulus while maintaining a comparable or slightly superior damping capacity to that of matrix alloys. Considering the very different effects of graphite and SiC particles on the properties of Al alloys, SiC and graphite particle hybrid reinforced 6061 Al MMCs (6061Al/SiC/Gr) were fabricated using a spray deposition technique in an effort to develop a high damping and high modulus material. Two ratios of SiC to graphite particle volumes were used to explore optimal combination of damping and modulus of the hybrid MMCS. Both damping capacity and storage modulus were evaluated on a dynamic mechanical thermal analyzer. Experimental results showed that the 6061Al/SiC/Gr hybrid MMCs exhibited a higher damping than the 6061/SiC and a higher modulus than 6061/Gr MMCs with similar volume fraction of reinforcement. The operative damping mechanisms are discussed on the basis of microstructural analyses. The improvement in damping capacity of the hybrid MMCs is discussed in terms of microstructural modification in the matrix and generation of interfaces due to the presence of SiC and graphite particles.

• OSTI ID: 62980
• Report Number(s): CONF-941016--; ISBN 0-87339-247-7
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM BASE ALLOYS
CHROMIUM ADDITIONS
COMPOSITE MATERIALS
COPPER ADDITIONS
DAMPING
DEPOSITION
DISLOCATIONS
EXPERIMENTAL DATA
EXTRUSION
GRAIN BOUNDARIES
GRAPHITE
INTERFACES
MAGNESIUM ALLOYS
MICROSTRUCTURE
OPTICAL MICROSCOPY
PARTICULATES
SCANNING ELECTRON MICROSCOPY
SILICON ADDITIONS
SILICON CARBIDES