| 2003 №09 (11) | 2003 №09 (02) |
The Paton Welding Journal, 2003, #9, 2-4 pages
Allowance for effect of cycle asymmetry on cyclic crack resistance of materials and welded joints
V.S. Kovalchuk
E.O. Paton Electric Welding Institute of the NASU 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.Abstract
It was established from the results of investigations of high-strength steel welded joints that increase in values of the coefficient of asymmetry from 0 to 0.5 leads to the 3-4 times increase in rate of fatigue crack propagation at the initial region of a mean-amplitude area of kinetic diagrams of fatigue fracture and has almost no effect at its final region. Based on the analysis of these and literature data, the method and analytical expressions are suggested allowing the cycle asymmetry to be taken into account within wide ranges in determination of a cyclic crack resistance using a limited number of initial parameters.
Keywords: cyclic crack resistance, cycle asymmetry, welded joints, calculation
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