EFFECTS OF ENVIRONMENT ON THE FRACTURE BEHAVIOR OF TITANIUM AND ITS ALLOYS.

Abstract

A study was made of the mechanisms of stress-corrosion cracking (SCC) of titanium and Ti-Al alloys in methanol-iodine solutions. The path of cracking was found to depend on the composition of the alloy. In pure titanium and a Ti-2.09 w/o Al alloy SCC is intergranular. In higher alloys (> 5 w/o Al) only the initial part of the crack is intergranular, the later formed transgranular propagation stage exhibiting cleavage markings. Comparative studies of corrosion behavior, characteristics of SCC, and metallurgical factors (i.e. alloy composition and deformation characteristics) indicated that two mechanisms may be operative. The intergranular SCC process appears to involve stress-accelerated corrosion, while the transgranular process exhibits the characteristics of cleavage and appears to be related to a reduced propensity for cross-slip. Comparison of the SCC behavior in methanol-iodine solutions with that in a methanol-hydrochloric acid solution indicates that similar processes are operative in the latter solution. (Author)

Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1968
Accession Number
AD0674255

Entities

People

  • A. J. Sedriks
  • E. N. Pugh

Organizations

  • Martin Marietta

Tags

Communities of Interest

  • Materials and Manufacturing Processes

DTIC Thesaurus Topics

  • Acids
  • Alcohols
  • Chemical Compounds
  • Corrosion
  • Cracks
  • Environment
  • Hydrochloric Acid
  • Material Degradation Processes
  • Methanols
  • Stress Corrosion
  • Stress Corrosion Cracking
  • Titanium

Fields of Study

  • Materials science

Readers

  • Materials Science (Mechanical Engineering).
  • Materials Science and Engineering.