Structural Stability of a Cast Co-Cr-Mo-Alloy During Impulsive Thermal- Mechanical Loading

Abstract

The response of a cast cobalt-base alloy to impulsive thermal- mechanical fatigue conditions, present during the firing of automatic weapons, was examined. The study indicates that a variety of structural alterations take place near the interior gun bore surface that are dependent upon the firing schedule and the ammunition used. Surface-layer melting and Stage I type of fatigue cracks are noted for the larger caliber inserts. Extensive slip- deformation and work-hardening in the surface areas were attributed to the interior ballistics conditions as well as to the prior machining operations. The stress-induced transformation phenomenon in the matrix and the precipitation in the slip zones related to the enhancement of wear resistance are discussed.

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Document Details

Document Type
Technical Report
Publication Date
Dec 01, 1970
Accession Number
AD0721895

Entities

People

  • William T. Ebihara

Tags

Communities of Interest

  • Weapons Technologies

DTIC Thesaurus Topics

  • Automatic Weapons
  • Ballistics
  • Chemical Reactions
  • Crack Propagation
  • Crack Tips
  • Crystal Structure
  • Double Base Propellants
  • Engineering
  • Grain Boundaries
  • Gun Barrels
  • Materials
  • Mechanical Working
  • Orientation (Direction)
  • Plastic Deformation
  • Precipitation
  • Propellants
  • Wear Resistance

Fields of Study

  • Materials science

Readers

  • Mechanical Engineering/Mechanics of Materials.
  • Tribology (the study of the boundary interaction between sliding surfaces, lubrication, wear and friction).
  • ballistics.