Characterization of anisotropic elastic constants of silicon-carbide particulate reinforced aluminum metal matrix composites; Part 1: Experiment

Journal Article · Fri Apr 01 00:00:00 EST 1994 · Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (United States)

OSTI ID:7085118

Jeong, H ^[1]; Hsu, D K ^[2]; Shannon, R E ^[3]; Liaw, P K ^[4]

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1. Agency for Defense Development, DaeJon (Korea, Republic of)
2. Iowa State Univ., Ames, IA (United States). Center for Nondestructive Evaluation
3. Westinghouse Science Technology Center, Pittsburgh, PA (United States). Materials Reliability Dept.
4. Univ. of Tennessee, Knoxville, TN (United States). Dept. of Materials Science and Engineering

The anisotropic elastic properties of silicon-carbide particulate (SiC[sub p]) reinforced Al metal matrix composites were characterized using ultrasonic techniques and microstructural analysis. The composite materials, fabricated by a powder metallurgy extrusion process, included 2124, 6061, and 7091 Al alloys reinforced by 10 to 30 pct of [alpha]-SiC[sub p] by volume. Results were presented for the assumed orthotropic elastic constants obtained from ultrasonic velocities and for the microstructural data on particulate shape, aspect ratio, and orientation distribution. All of the composite samples exhibited a systematic anisotropy: the stiffness in the extrusion direction was the highest, and the stiffness in the out-of-plane direction was the lowest. Microstructural analysis suggested that the observed anisotropy could be attributed to the preferred orientation of SiC[sub p]. The ultrasonic velocity was found to be sensitive to internal defects such as porosity and intermetallic compounds. It has been observed that ultrasonics may be a useful, nondestructive technique for detecting small directional differences in the overall elastic constants of the composites since a good correlation has been noted between the velocity and microstructure and the mechanical test. By incorporating the observed microstructural characteristics, a theoretical model for predicting the anisotropic stiffnesses of the composites has been developed and is presented in a companion article (Part 2).

• OSTI ID: 7085118
• Journal Information: Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (United States), Vol. 25:4; ISSN 0360-2133
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM ALLOYS
ELASTICITY
COMPOSITE MATERIALS
SILICON CARBIDES
MATHEMATICAL MODELS
MICROSTRUCTURE
ULTRASONIC TESTING
ACOUSTIC TESTING
ALLOYS
CARBIDES
CARBON COMPOUNDS
MATERIALS
MATERIALS TESTING
MECHANICAL PROPERTIES
NONDESTRUCTIVE TESTING
SILICON COMPOUNDS
TENSILE PROPERTIES
TESTING
360603* - Materials- Properties