Accession Number : ADA305943

Title :   Ultrasonic Nondestructive Evaluation of Impact-Damaged Graphite Fiber Composite.

Descriptive Note : Contractor rept.,

Corporate Author : MASSACHUSETTS INST OF TECH CAMBRIDGE

Personal Author(s) : Williams, James H., Jr. ; Lampert, Norman R.

PDF Url : ADA305943

Report Date : MAY 1980

Pagination or Media Count : 23

Abstract : Unidirectional Hercules As/3501-6 graphite fiber epoxy composites are subjected to repeated controlled low-velocity drop-weight impacts in the laminate direction. The degradation is ultrasonically monitored using through-thickness attenuation and a modified stress wave factor, SWF. There appear to be strong correlations between the number of drop-weight impacts, the residual tensile strength, the through-thickness attenuation and the SWF. The results are very encouraging with respect to the NDE potential of both of these ultrasonic parameters to provide strength characterizations in virgin as well as impact-damaged fiber composite structures. (MM)

Descriptors :   *FIBER REINFORCED COMPOSITES, *GRAPHITE, TENSILE STRENGTH, NONDESTRUCTIVE TESTING, DEGRADATION, POLYMERS, LAMINATES, STIFFNESS, DAMAGE ASSESSMENT, ORIENTATION(DIRECTION), FABRICATION, STRENGTH(MECHANICS), IMPACT STRENGTH, DEFECTS(MATERIALS), DROP TESTS, FAILURE(MECHANICS), ULTRASONIC TESTS, STRESS WAVES, GRAPHITE EPOXY COMPOSITES, UNIDIRECTIONAL.

Subject Categories : Laminates and Composite Materials

Distribution Statement : APPROVED FOR PUBLIC RELEASE