EFFECTS OF PRESTRAINING UNDER HYDROSTATIC PRESSURE ON THE MECHANICAL BEHAVIOR OF POLYCRYSTALLINE BERYLLIUM.

Abstract

The effects of hydrostatic pressure up to 400 ksi and at 25 C to 300 C on the mechanical properties of three forms of beryllium (hot-pressed block, extruded rod and cross-rolled sheet) were investigated. Three effects of pressure were studied: mechanical behavior under pressure, the effect of pressure cycling on the subsequent atmospheric pressure mechanical properties and the effects of prestraining under hydrostatic pressure on the subsequent atmospheric pressure mechanical properties. Pressure cycling did not produce a significant improvement in the tensile ductility of the hot-pressed and the extruded materials; it did, however, given an improvement in the tensile and bend ductility of the sheet. With the possible exception of an improvement in the bend ductility of sheet, tensile prestraining under hydrostatic pressure either produced no change in the subsequent atmospheric pressure ductility or there resulted a decrease. The prestraining did, however, give an increase in yield and fracture stresses. The results obtained in the present investigation suggest that the principal effect of pressure is on the fracture stress rather than on the flow stress. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1967
Accession Number
AD0813874

Entities

People

  • H. Conrad
  • J. E. Hanafee
  • N. Inoue
  • V. V. Damiano

Organizations

  • Franklin Institute

Tags

DTIC Thesaurus Topics

  • Barometric Pressure
  • Beryllium
  • Ductility
  • Elastic Properties
  • Hydrostatic Pressure
  • Materials
  • Mechanical Properties
  • Mechanics
  • Physical Properties
  • Polycrystals

Readers

  • Metallurgy