DEEP DRAWN AUSFORMING DEVELOPMENT PROGRAM. 12 DIA. ROCKET MOTOR CHAMBERS
Abstract
An ausforming program was conducted to develop and apply the technique of hot-working in the austenitic phase of Tricent M-300 steel on deep drawn 1-piece 11.65-in.-diam by about 36-in.long rocket motor chambers. An attempt will be made to include the forward dome as well as the cylindrical sidewall in an effort to achieve a uniaxial 0.2% off-set yield strength level of 400,000 psi. Twenty-five forged billets of double vacuum melted M-300 steel macro etched in 50% HCl at 160 F were suitable for the pancaking operation. Chemical analysis and metallographic examination of non-metallic inclusions and the normalized structure were made after the pancaking and normalizing operations. About 0.100 in. of material was machined from all surfaces of the pancakes to provide 25.5-in.-diam by 0.820-in.-thick blanks for the hot cupping operation. Elevated temperature tensile tests were made on the M-300 steel to determine strength and ductility in the hot austenitic condition. Examination of the fractured specimens revealed a banded microstructure of untempered martensite, intergranular free ferrite, and bainite.
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 30, 1961
- Accession Number
- AD0257340
Entities
People
- Wayne A. Martin