Determining the Load-Time History of Fiber Composite Materials by Acoustic Emission,

Abstract

Acoustic emission was monitored during the axial loading of unidirectional fiber composite tensile specimens. The material consisted of strong, brittle fibers (E glass) imbedded in a viscoelastic matrix (epoxy). It was found that when the load was held constant the acoustic emission output continued, but at a decreasing rate with time at load. As the load level was increased, the acoustic emission output at load continued for a longer period. It is suggested that the acoustic emission under constant load is a result of fibre fracture which continues after loading ceases because of the viscoelastic nature of the matrix which allows stress redistribution with time. The experimental results from acoustic emission are compared with computer calculations for fibre fracture based on theoretical considerations. Good agreement is noted between the theoretical and experimental results. (Author)

Document Details

Document Type
Technical Report
Publication Date
Mar 01, 1974
Accession Number
AD0780122

Entities

People

  • A. Rotem
  • J. Baruch

Organizations

  • Technion – Israel Institute of Technology

Tags

DTIC Thesaurus Topics

  • Acoustic Emissions
  • Agreements
  • Composite Materials
  • Computers
  • Emission
  • Materials

Readers

  • Marine Mammal Biology
  • Mechanical Engineering/Mechanics of Materials.
  • Optical Physics and Photonics.