Micromechanisms of fatigue crack growth and fracture toughness in metal-matrix composites. Technical report, 1 August-31 December 1988

Technical Report · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6086276

Davidson, D L

A detailed micromechanics analysis was performed on a composite of 2014 aluminum alloy matrix with 15 vol.% particulate SiC. This composite was manufactured by the Dural Co. by casting and extrusion. The matrix alloy was peak aged before testing. The microstructure was found to contain about 3% intermetallic particles in addition to those expected for this material. Fatigue cracks were grown from approximately threshold to rapid fracture stress intensities. Fatigue cracks growth rates and fracture toughness were measured. Analyses of the crack tips were performed by stereoimaging at low and intermediate stress intensities, and just prior to the onset of rapid fracture. Detailed strain maps were derived, and considerable influence of SiC on strain was found. Analyses of microcracks near the main crack were made and found to have only a small influence on fracture.

• Research Organization: Southwest Research Inst., San Antonio, TX (USA)
• OSTI ID: 6086276
• Report Number(s): AD-A-203593/9/XAB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360603* -- Materials-- Properties
ALLOYS
ALUMINIUM ALLOYS
CARBIDES
CARBON COMPOUNDS
COMPOSITE MATERIALS
CRACK PROPAGATION
CRACKS
CRYSTAL STRUCTURE
DOCUMENT TYPES
EXTRUSION
FABRICATION
MATERIALS
MATERIALS WORKING
MATRIX MATERIALS
MECHANICS
MICROSTRUCTURE
PARTICLES
PARTICULATES
PROGRESS REPORT
SILICON CARBIDES
SILICON COMPOUNDS
STRESSES