AN INVESTIGATION OF THE CRACK-PROPAGATION OF HIGH STRENGTH ALLOYS AND HEAT RESISTANT ALLOYS
Abstract
An investigation was made to determine the crack-propagation resistance of super-alloy and refractory-metal sheet materials and to investigate certain aspects of the elevated-temperature mechanical behavior of high-strength low-alloy steels. Sheet specimens containing central transverse fatigue cracks were used in the experimental work. It was found that the fracture toughness of the nickel-base alloys-Rene' 41, Nimonic 90, Inconel-X and Unitemp 1753-decreased slightly in the temperature range from about 1000 to 1400 F, in which temperature range there were generally increases in ultimate tensile strength and decreases in tensile elongation. The alloys A286 (iron bases) and L606 (cobalt base) did not show this brittleness tendency. Among the refractory metals, unalloyed molybdenum was found to have a brittle-ductile transition temperature of about 150 F; the molybdenum alloys-Mo-1/2%Ti and TZM- both had transition temperatures of about 65 F. Unalloyed tungsten sheet, containing sharp notches rather than fatigue cracks, showed an increasing tendency to brittleness below about 500 F.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 21, 1962
- Accession Number
- AD0290278
Entities
People
- J. D. Morrison
- J. R. Kattus
- P. C. Jenkins
Organizations
- Southern Research