Crack propagation in some high strength materials
No Thumbnail Available
Date
1981-11-12
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Australian Institute of Nuclear Science and Engineering
Abstract
"Fatigue life" predictions based on a fracture mechanics approach assume that cracks are initially present in a structure or initiate early in service. These cracks propagate during cyclic stress at a rate which
is a function of the fluctuation in stress intensity factor at the crack tip.
Instantaneous fracture toughness, to allow determination of critical crack size, and fatigue crack propagation rate have been measured for aluminium 7075 alloy, maraging 300 and 350 grade steels and magnetic P6 grade steels.
Except for magnetic P6 grade steels, the annealed and aged materials were found to have essentially the same crack propagation rates, this confirms and extends a similarity reported for annealed and aged maraging 300 grade steel.
The aged, high strength alloys are used for disc shaped rotating components. By combining a stress intensity factor analysis for flat discs containing a central, notched borehole with a commonly used
fatigue crack propagation law, the interaction between fracture toughness, fatigue properties, notch size and speed of rotation has been used to examine life expectancy of components in terms of number of run up - run down cycles.
Description
Physical copy held by ANSTO Library at DDC: 621.48/78
Keywords
Fatigue, Fracture mechanics, Cracks, Crack propagation, Stress analysis, Steels, Annealing, Boreholes
Citation
Clare, T. E. (1981). Crack propagation in some high strength materials. Presentation to the 3rd AINSE Engineering Conference, 12-13th November 1981, AINSE Theatre, Lucas Heights. In 3rd AINSE Engineering Conference, 12 - 13th November 1981, AINSE Theatre, Lucas Heights handbook: conference handbook(programme, abstracts and general information), (pp. 8). Lucas Heights, Sydney : Australian Institute of Nuclear Science and Engineering.