Thermochemical Model of Hydrogen Cracking at Heat-Affected Cannon Bore Surfaces
Abstract
Two examples of hydrogen cracking in the heat-affected region of fired cannons are given, including metallographic evidence of damage at various depths near the bore surface. The depth of steel transformation due to firing is used to verify near-bore temperature distributions and transient and residual stress distributions calculated using classic one-dimensional heat flow analysis. Predicted depths of thermal damage and hydrogen cracks compare well with observed depths for different crack orientations and firing temperatures. Laboratory fracture mechanics tests using bolt-load compact specimens are described, including crack growth and blunt-notched tests in acid-hydrogen environments. The utility of the thermal and fracture mechanics analyses and the laboratory fracture mechanics tests used with cannons are discussed for weld applications.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 01, 1999
- Accession Number
- ADA368087
Entities
People
- E. Troiano
- G. N. Vigilante
- John H. Underwood
Organizations
- United States Army Armament Research, Development and Engineering Center