A Metallographic Study of White Layers in Gun Steel

Abstract

A metallographic investigation has been made of the white layers formed on the bore surface of a fired Army and Navy cannon and those produced in gun steel specimens in laboratory where firing conditions were simulated. White layers are produced in laboratory specimens in reducing environments (e.g. methane gas) but not in argon or nitrogen and appear similar to those produced in the fired cannons. These are formed at the melting as well as lower temperatures. The effects of increase in the pressure of the environment appears first to aid the formation of white layers and furthermore to increase their thickness. These results and the earlier studies of the characterization of white layers from fired cannons suggests that carbon from the gaseous environment of the propellant combustion products and the pressures of gases have significant effects on the formation and growth of white layers. The white layers produced in the Navy cannon where NACO, low flame temperature propellant was used are compared with those produced in the Army cannons where high flame temperature propellant was used. These observations are also discussed. (Author)

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Document Details

Document Type
Technical Report
Publication Date
Aug 01, 1978
Accession Number
ADA060604

Entities

People

  • Ann Campbell
  • M. H. Kamdar
  • T. Brassard

Organizations

  • United States Army Armament Research, Development and Engineering Center

Tags

DTIC Thesaurus Topics

  • Aluminum Oxides
  • Carbon Dioxide
  • Carbon Monoxide
  • Classification
  • Combustion
  • Combustion Products
  • Dielectric Gases
  • Environment
  • Gases
  • Gun Barrels
  • High Pressure
  • High Temperature
  • Materials
  • Materials Laboratories
  • Military Research
  • Propellants
  • Security

Fields of Study

  • Physics

Readers

  • Combustion science or combustion engineering.
  • Munitions and Ordnance Engineering
  • Rocket Propulsion.