Micromechanisms of crack growth and fracture toughness in metal matrix composites. Technical report, 29 April 1985

Technical Report · Sun Jun 01 04:00:00 EDT 1986

OSTI ID:5039305

Davidson, D L; Lankford, J; Leverant, G R

Subcritical crack growth and rapid fracture of the mechanically alloyed aluminum alloy IN-9052 reinforced with SiC particles were investigated. Fatigue crack growth rates for the composite exceed those of the unreinforced alloy, except that the threshold stress intensity for growth is higher for the composite. Fracture toughness of the composite is about 9 square root of M cubed compared to a (reported) value of 29 square root of M cubed for the unreinforced alloy. The contributions to fracture toughness from work done within the plastic zone and in formation of the void sheet were computed using analytical models. Fracture toughness is shown to result almost entirely from work done within the plastic zone of the growing crack. The matrix microstructure and the particle characteristics are found to account for the elastic and fracture properties of this composite.

• Research Organization: Southwest Research Inst., San Antonio, TX (USA)
• OSTI ID: 5039305
• Report Number(s): AD-A-169839/8/XAB; SWRI-06-8602
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360303* -- Composite Materials-- Mechanical Properties-- (-1987)
ALLOYS
ALUMINIUM ALLOYS
CARBIDES
CARBON COMPOUNDS
COMPOSITE MATERIALS
CRACK PROPAGATION
CRYSTAL STRUCTURE
FRACTURE PROPERTIES
MATERIALS
MATHEMATICAL MODELS
MATRIX MATERIALS
MECHANICAL PROPERTIES
MICROSTRUCTURE
SILICON CARBIDES
SILICON COMPOUNDS