The Mechanical Behavior of Polystyrene under Pressure,

Abstract

Tensile deformation of polystyrene carried out under pressure up to 4 kb has shown that the pressure-transmitting fluid (silicon oil) acts as a stress crazing and cracking agent. Analysis of the stress-strain curves for the sealed specimens indicated that the pressure dependency of the craze initiation stress differs from that of shear band initiation stress. The brittle to ductile transition occurs when the initiation stresses of both processes become equal. The principal stress for craze initiation showed almost no pressure dependency, suggesting that crazes initiate when the principal stress level of the tensile specimen reaches a critical value irrespective of the applied hydrostatic pressure. Similarly, no pressure dependency was observed for the principal ductile fracture stress. The pressure dependency of yield stress agreed well with a non-linear pressure dependent von Mises yield criterion.

Document Details

Document Type
Technical Report
Publication Date
Sep 13, 1974
Accession Number
ADA002329

Entities

People

  • E. Baer
  • K. Matsushige
  • S. V. Radcliffe

Organizations

  • Case Western Reserve University

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Dielectric Polymers
  • Hydrostatic Pressure
  • Mechanical Properties
  • Physical Properties
  • Polystyrenes
  • Shear Bands
  • Stress Strain Relations
  • Stresses
  • Transitions
  • Transmitting

Fields of Study

  • Engineering

Readers

  • Materials Science (Mechanical Engineering).
  • Mechanical Engineering/Mechanics of Materials.