METALLURGICAL CHARACTERISTICS OF HIGH STRENGTH STRUCTURAL MATERIALS
Quarterly progress rept. no. 11, Apr-Jun 1966
NAVAL RESEARCH LAB WASHINGTON DC
Pagination or Media Count:
A progress report covering the research studies in high strength structural metals conducted during the period April through June 1966 is presented. The report includes fracture toughness studies on specially melted 18 Ni grade 250 ksi maraging steel and a Cr-Ni-Mo stainless steel. Welding studies on a 12Ni-5Cr-3Mo maraging steel with 12Ni-3Cr-3Mo filler metal wire are described with the problems associated with developing optimum properties in both plate and weldment being discussed. Results of fracture toughness studies on titanium alloys and aluminum alloys are presented in which engineering type tests and fracture mechanics techniques are employed. The fracture toughness index diagrams for steels and titanium are presented based upon the correlations developed with the engineering test methods. Preliminary fracture toughness correlation diagrams are presented for titanium alloys based upon fracture mechanics test methods. Results of a study on the low cycle fatigue crack propagation of a 9Ni-4Co-0.25C steel in air and salt water is discussed and compared to similar data obtained for other steels covering a spectrum of yield strengths. Stress-corrosion-cracking studies were conducted on titanium alloys, aluminum alloys, and steels.
- Metallurgy and Metallography