ISSN:
1013-9826
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
In order to investigate the effect of frequency on the crack growth behavior,ultrasonic fatigue tests were carried out for an extruded age-hardened Al alloy, 7075-T6, andthe results were compared with those in rotating bending fatigue. Fatigue strength in ultrasonicwas higher than that in rotating bending. This was mainly caused by the retardation of crackinitiation. Growth direction of a crack changed from a tensile mode to a shear one in ultrasonicfatigue, though fracture occurred by the growth of a tensile mode in rotating bending. Thegrowth direction of a shear mode crack was inclined about 55 degrees to the tensile axis. Therelation between an applied stress σa and a crack depth at transition of growth direction [removed info]T[removed info]was expressed by [removed info]an[removed info]T=C, where C and n are constants. These results were discussed fromthe points of view of the time dependent environmental effect and the texture of material
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/52/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.324-325.327.pdf
