DEVELOPMENT OF ULTRA HIGH STRENGTH ROCKET MOTOR CASES BY CRYOGENIC STRETCH FORMING
Abstract
The fundamental aspects of cryogenic stretch forming as applied to the fabrication of ultrahigh strength rocket cases of various configurations were investigated. In this process, pressure vessels made of 301 stainless steel by conventional roll and weld techniques, are stretched to final size and shape by internal pressurization at -320 F. A maximum nominal ultimate strength of 284,000 psi at room temperature was achieved in one case. In other cases a strength level of 260,000 psi was readily attained. It was also shown that close dimensional control of cylindrical cases can be accomplished by stretch forming in a die. A metallurgical investigation was performed to determine the effect of type and composition of materials on their behavior in the cryogenic stretch forming process. Strength levels of 325,000 psi were achieved in tensile coupon tests. Uniaxial tensile tests of materials utilized in case fabrication were correlated with the plastic flow behavior of these materials when stretched biaxially. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 15, 1962
- Accession Number
- AD0271915
Entities
People
- R.h. Alper