Accession Number : AD0718360

Title :   Deformation and Fracture in Al-CuAl2 Eutectic Composites.

Descriptive Note : Technical rept.,

Corporate Author : DREXEL UNIV PHILADELPHIA PA DEPT OF METALLURGICAL ENGINEERING

Personal Author(s) : Pattnaik,A. ; Lawley,A.

Report Date : JAN 1971

Pagination or Media Count : 29

Abstract : Ambient temperature compressive stress-strain behavior to failure, and associated structural detail, were characterized in Al-CuAl2 composites of small interlamellar spacing (< or = 2 microns). Differences in the compressive and tensile yield stress levels of the composite are attributed to thermally induced residual stress. Analysis gives a residual tensile stress of about 3500 psi and an in-situ yield stress of about 13,500 psi in the aluminum-rich phase. Evidence for a dislocation-interface interaction is provided by the form of deformation substructure in the aluminum-rich phase. Failure in these multi-grained eutectic composites is shown to be controlled primarily by shear-mode buckling of the lamellar structure. Buckling leads to cleavage of the CuAl2 phase, shear in the aluminum-rich phase, accompanied by void formation, coalescence and crack formation. (Author)

Descriptors :   (*COMPOSITE MATERIALS, *ALUMINUM), (*REINFORCING MATERIALS, *INTERMETALLIC COMPOUNDS), ALUMINUM ALLOYS, COPPER ALLOYS, MICROSTRUCTURE, ELECTRON MICROSCOPY, GRAIN BOUNDARIES, DISLOCATIONS, MECHANICAL PROPERTIES

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE