Accession Number : AD0282379

Title :   RESEARCH AND DEVELOPMENT OF TITANIUM ROCKET MOTOR CASE

Corporate Author : PRATT AND WHITNEY AIRCRAFT EAST HARTFORD CONN

Personal Author(s) : HAUSER,H.A. ; HELFRICH,W.E.

Report Date : 30 APR 1962

Pagination or Media Count : 1

Abstract : OXYGEN CONTENTS IN THE 0.10-0.20 PER CENT RANGE DO NOT SERIOUSLY IMPAIR THE SMOOTH AND NOTCHED (K sub t = 8) tensile ductility at -40F of pressforged material aged to the 180,000-190,000 psi room temperature yield strength level. Singlepass TIG welds made with parent metal hydrogen contents in excess of 300 ppm display a high incidence of weld porosity and premature failures under cyclic sustained tensile loads. Excellent fracture toughness can be achieved in singlepass TIG welds by cold rolling (50% reduction) and subsequent annealing at 1450F. A reduction in forging temperature (final operation) from 1850F to 1800F significantly improves the tensile ductility of a full scale 40-inch diameter rear dome press-forged in closed dies (three steps) by the dogbone technique. Press forging of full scale 40-inch diameter rear domes in closed dies (three steps) by the dogbone method at 1800-1850F produces anisotropy in tensile properties after aging to the 180,000 psi minimum yield strength level. Higher strength and lower elongations are observed in the tangential as compared to radial direction. (Author)

Descriptors :   *ROCKET ENGINE CASES, *TITANIUM ALLOYS, ALUMINUM ALLOYS, CHROMIUM ALLOYS, ELECTRON BEAMS, FORGING, HEAT TREATMENT, MANUFACTURING, MECHANICAL PROPERTIES, MICROSTRUCTURE, TENSILE PROPERTIES, VANADIUM ALLOYS, WELDING

Distribution Statement : APPROVED FOR PUBLIC RELEASE