A study of laser-generated Rayleigh and Lamb waves in graphite/epoxy composites

Miscellaneous · Tue Jan 01 00:00:00 EST 1991

OSTI ID:6978019

Heeyong, Park

This study explores the potential for application of laser generated Rayleigh and Lamb waves in graphite/epoxy composites. Numerical results are obtained by the solution of the wave equations using assumed solutions, and enforcing the boundary conditions. Experimentally, Rayleigh and Lamb waves were generated by a Q-switched ruby laser in the ablation regime and detected by piezoelectric pinducers which permitted accurate phase-velocity measurements. The Rayleigh wave velocity was measured at various directions relative to the fiber direction and results were found to agree closely with numerical predictions. The increase of surface wave velocity using thin plates could be useful for the application of delamination detection in thick composites, and an increase of Rayleigh wave attenuation could indicate damages caused by impact. Also, surface waves can reflect from small surface cracks. Therefore, laser generated surface waves, particularly along the fiber direction, have high potential for application in non-destructive testing.

• Research Organization: Oregon State Univ., Corvallis, OR (United States)
• OSTI ID: 6978019
• Resource Relation: Other Information: Thesis (Ph.D.)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
42 ENGINEERING
COMPOSITE MATERIALS
NONDESTRUCTIVE TESTING
EPOXIDES
GRAPHITE
RAYLEIGH WAVES
WAVE EQUATIONS
CARBON
DIFFERENTIAL EQUATIONS
ELEMENTAL MINERALS
ELEMENTS
EQUATIONS
MATERIALS
MATERIALS TESTING
MINERALS
NONMETALS
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
PARTIAL DIFFERENTIAL EQUATIONS
SEISMIC SURFACE WAVES
SEISMIC WAVES
TESTING
360603* - Materials- Properties
420500 - Engineering- Materials Testing