Yield Pressure Measurements and Analysis for Autofrettaged Cannons
Abstract
Yield pressure for a small permanent strain was measured in quasi-static laboratory tests of autofrettaged ASTM A723 steel cannon pressure vessels. Yield pressure was found to be a consistent ratio of the yield strength measured in close proximity to the area of observed yielding. Comparable yield pressure measurements for cannons firing with typical 5-ms pressure pulse duration gave 14% higher yield pressures, attributed to strain%rate effects on plastic deformation. Calculated von Mises' yield pressure for the laboratory test conditions, including the Bauschinger-modified inner diameter residual stress and open- end vessel conditions, agreed with measured yield pressure within 3 to 5 %. Calculated yield pressure was found to be insensitive to the value of axial residual stress, since it is typically the intermediate value in the von Mises' yield criterion. A description of yield pressure normalized by yield strength was given for autofrettaged A723 open-end pressure vessels over a range of wall ratio and degree of autofrettage, including effects of Bauschinger-modified residual stress. This method for calculating yield pressure is proposed as a design procedure for cannons and other pressure vessels.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 01, 2002
- Accession Number
- ADA402335
Entities
People
- Anthony P. Parker
- David B. Moak
- John H. Underwood
- Michael A. Audino
Organizations
- United States Army Armament Research, Development and Engineering Center