SYMPOSIA PAPER Published: 01 January 1985
STP32819S

Elastic Representation Surfaces of Unidirectional Graphite/Epoxy Composites

Source

Unidirectional graphite/epoxy composites exhibit high elastic anisotropy and unusual geometrical features in their elastic-property polar diagrams. From the five-component transverse-isotropic elastic-stiffness tensor we compute and display representation surfaces for Young's modulus, torsional modulus, linear compressibility, and Poisson's ratios. Based on Christoffel-equation solutions, we describe some unusual elastic-wave-surface topological features. Musgrave considered in detail the differences between phase-velocity and group-velocity surfaces arising from high elastic anisotropy. For these composites, we find effects similar to, but more dramatic than, Musgrave's. Some new, unexpected results for graphite/epoxy include: a shearwave velocity that exceeds a longitudinal-wave velocity in the plane transverse to the fiber; a wave that changes polarization character from longitudinal to transverse as the propagation direction sweeps from the fiber axis to the perpendicular axis.

Author Information

Kriz, RD
Fracture and Deformation Division, Center for Materials Science, National Bureau of Standards, Boulder, CO
Ledbetter, HM
Fracture and Deformation Division, Center for Materials Science, National Bureau of Standards, Boulder, CO
Price: $25.00
Contact Sales
Related
Reprints and Permissions
Reprints and copyright permissions can be requested through the
Copyright Clearance Center
Details
Developed by Committee: D30
Pages: 661–675
DOI: 10.1520/STP32819S
ISBN-EB: 978-0-8031-4929-8
ISBN-13: 978-0-8031-0436-5