Embrittlement of Gun Steel by Copper
Abstract
Metallographic examination of the bore surfaces of cannon tubes revealed a close association of copper with the erosion and cracking that occurs during firing. Metallic copper, transferred by abrasive contact between the steel surface and the copper rotating band on the projectile that engages the rifling, can induce embrittlement and enhance propagation of cracks developed by the thermal-mechanical stresses generated during firing. Corroborative experiments using capacitance discharge heating verified that copper-induced embrittlement and cracking can occur during a thermal pulse of only a few milliseconds duration. Hot tensile testing with a Gleeble machine confirmed that copper penetrates austenite grain boundaries causing hot tearing in just a few seconds at 1000 C, i.e., well below the melting point of copper.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 1984
- Accession Number
- ADA145889
Entities
People
- A. Szirmae
- M. H. Kamdar
- R. M. Fisher
Organizations
- United States Army Armament Research, Development and Engineering Center