A STUDY OF THE NOTCHED-BAR CREEP-RUPTURE TEST.

Abstract

The uncertainty about the use of the Odqvist equations for strain predictions under biaxial tension with constant principal stress ratios and principal stress directions held fixed was resolved. Tests were run with varying stress ratios but no general conclusions were reached. Attempts to obtain a better understanding of creep-rupture by separating the initiation and propagation phases of fracture led to very encouraging results. Although the model used may turn out to be too simplified it appears to explain a number of features of creep-rupture in smooth and notched bars. Analytical studies on notched members were only partially successful. The study of the two-dimensional case of a flat strip with notches was completed, but the three-dimensional case of a rod with a circumferential notch was abandoned. Numerical solution of three-dimensional elastic-plastic or elastic-creep problems turned out generally to be more difficult than anticipated. This is unfortunate for experiments on notched strips cannot simulate the constraint present in the case of circumferentially notched rods.

Document Details

Document Type
Technical Report
Publication Date
Sep 30, 1967
Accession Number
AD0661322

Entities

People

  • I. Finnie

Organizations

  • University of California, Berkeley

Tags

DTIC Thesaurus Topics

  • Equations
  • Geometry
  • Mathematics
  • Three Dimensional
  • Two Dimensional
  • Uncertainty

Readers

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