EXPLORATION AND EVALUATION OF NEW GLASSES IN FIBER FORM

Abstract

The strength of E- and S-glass fibers was investigated by tensile tests and static fatigue (constant load) tests. The principal variables were: gage length, strain rate, applied stress in static fatigue, and humidity. The gage length study led to identification of two types of surface flaws and a structural flaw type related to the heterogeneity of the glass network. Severity and distribution of flaws were derived from failure probability plots and strength-length plots at one strain rate in laboratory atmosphere. The effects of strain rate and of humidity on the flaw characteristics was studied. Extensive static fatigue tests provided insight into the stress corrosion processes. Fibers retained the initial tensile strength over 95 percent of the static fatigue exposure. It was postulated that chemical events during this incubation period had to reach a critical stage before stress corrosion could occur, and that corrosion originated on sites of structural flaws located near the surface. These findings are in disagreement with the current theory on stress corrosion and a new model is proposed.

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Document Details

Document Type
Technical Report
Publication Date
May 20, 1965
Accession Number
AD0464261

Entities

People

  • Gunther K. Schmitz

Tags

Communities of Interest

  • Space
  • Weapons Technologies

DTIC Thesaurus Topics

  • Air Force
  • Contracts
  • Distribution Curves
  • Distribution Functions
  • Fatigue Tests (Mechanics)
  • Glass Fibers
  • Material Degradation Processes
  • Materials
  • Measurement
  • Mechanics
  • Resistance
  • Standards
  • Stress Concentration
  • Stress Corrosion
  • Tensile Strength
  • Test And Evaluation
  • Test Equipment

Readers

  • Materials Science and Engineering.
  • Reinforced Composite Materials
  • Theoretical Analysis.