EFFECTS OF HYDROGEN TREATMENT ON THE DUCTILITY OF MOLYBDENUM UNDER 760 AND 10 TO THE MINUS 10TH POWER TORR.

Abstract

Room-temperature tensile experiments on polycrystalline molybdenum indicate a grain size and heat treatment contribution to the difference in strain-to-fracture of specimens deformed at 760 Torr to those deformed at 10 to the -10th power Torr. The magnitude of the effect appears to depend critically on grain size and impurity distributions resulting from heat treatment with and without a hydrogen atmosphere. However, it has been determined that the ductility effects are predominantly due to a change in ductility of specimens tested at atmospheric pressure. Ultrahigh vacuum tensile behaviors are relatively unaffected. The largest difference in strain-to-fracture (approximately 13%) was in a narrow grain-size range in which specimens were first recrystallized and then soaked in a hydrogen atmosphere. The enhancement of ductility of hydrogen-treated specimens under vacuum suggests the involvement of a hydrogen-related gaseous contaminant. (Author)

Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1967
Accession Number
AD0813026

Entities

People

  • Seymour Feuerstein

Organizations

  • The Aerospace Corporation

Tags

DTIC Thesaurus Topics

  • Atmospheres
  • Barometric Pressure
  • Ductility
  • Environmental Pollutants
  • Grain Size
  • Heat Treatment
  • Hydrogen
  • Impurities
  • Molybdenum
  • Polycrystals
  • Pressure Distribution
  • Ultrahigh Vacuum
  • Vacuum

Fields of Study

  • Materials science

Readers

  • Electrochemical Engineering/ Fuel Cell Technologies
  • Mathematics or Statistics
  • Powder metallurgy of Titanium alloys.