Accession Number : ADA189652

Title :   Damage Models for Delamination and Transverse Fracture.

Descriptive Note : Final technical rept. 15 Feb 84-14 Jun 87,

Corporate Author : TEXAS A AND M UNIV COLLEGE STATION MECHANICS AND MATERIALS CENTER

Personal Author(s) : Schapery, Richard A ; Goetz, Douglas P ; Lamborn, Mark J

PDF Url : ADA189652

Report Date : Aug 1987

Pagination or Media Count : 85

Abstract : Theoretical and experimental work on the deformation and fracture of fibrous composites with distributed damage is described. Emphasis is on establishing the existence of potentials analogous to strain energy and on using these so called work potentials in deformation and fracture studies. The difference between changing damage and constant damage processes is accounted for by using multivalued work potentials. Discussed first are investigations of flat rectangular bar specimens and thin walled tubes under axial and torsional loading. The limited amount of experimental data presently available on angle ply laminates confirms the existence of a potential even when there are large increases in microcracking. Next, path independence of the J integral is discussed. A study is then described in which the J integral is used to determine fracture energy for delamination in double-cantilevered beam specimens, some of which have a large percentage of off-axis fibers; the results are compared with fracture energies found by standard methods (which do not account for effects of distributed damage). Keywords: Composites, Damage, Delamination, Fracture, Fiber reinforced plastic.

Descriptors :   *COMPOSITE MATERIALS, *DEFORMATION, *FIBER REINFORCEMENT, *FRACTURE(MECHANICS), *REINFORCED PLASTICS, AXES, DAMAGE, DISTRIBUTION, ENERGY, EXPERIMENTAL DATA, FIBERS, J INTEGRALS, LOAD DISTRIBUTION, LOADS(FORCES), MICROCRACKING, MODELS, RECTANGULAR BODIES, STANDARDIZATION, THEORY, TORSION, TRANSVERSE

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE