Accession Number : ADA303013

Title :   A Study of the Stress Wave Factor Technique for the Characterization of Composite Materials.

Descriptive Note : Contract rept.,

Corporate Author : VIRGINIA POLYTECHNIC INST AND STATE UNIV BLACKSBURG DEPT OF ENGINEERING SCIEN CE AND MECHANICS

Personal Author(s) : Henneke, Edmund G., II ; Duke, John C., Jr. ; Stinchcomb, Wayne W. ; Govada, Anil ; Lemascon, Alan

PDF Url : ADA303013

Report Date : FEB 1983

Pagination or Media Count : 73

Abstract : A testing program has been undertaken to provide an independent investigation and evaluation of the stress wave factor technique for characterizing the mechanical behavior of composite laminates. The present report details some of the data which have been obtained after performing a very large number of tests to determine the reproducibility of the SWF measurement. It has been determined that, with some optimizing of experimental parameters, one can reproduce the SWF value to within +/-10%. Results are also given which show that, after careful calibration procedures, the lowest SWF value along the length of a specimen will correlate very closely to the site of final failure when the specimen is loaded in tension. Finally, using a moire interferometry technique, it was found that local regions having the highest in-plane strains under tensile loading also had the lowest SWF values. (AN)

Descriptors :   *EPOXY COMPOSITES, *STRESS WAVES, STRESS STRAIN RELATIONS, MICROSTRUCTURE, NONDESTRUCTIVE TESTING, STRESS ANALYSIS, STATIC LOADS, STRESS TESTING, TENSILE STRESS, STIFFNESS, STRENGTH(MECHANICS), FRACTURE(MECHANICS), INTERFEROMETRY, CORRELATION, ULTRASONICS, EPOXY LAMINATES, CALIBRATION, FAILURE(MECHANICS), SURFACE TENSION.

Subject Categories : Laminates and Composite Materials
      Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE