| 2007 №12 (02) | 2007 №12 (04) |
The Paton Welding Journal, 2007, #12, 15-18 pages
Kinetics of growth of non-through-thickness fatigue cracks in 03Kh20N16AG6 and 12Kh18N10T steels at different values of the coefficient of stress cycle asymmetry
V.V. Knysh, S.A. Solovej, A.Z. Kuzmenko
E.O. Paton Electric Welding Institute of the NASU. 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.Abstract
Based on experimental data kinetic diagrams of fatigue fracture of steels 03Kh20N16AG6 and 12Kh18N10T at different values of the coefficient of stress cycle asymmetry are plotted. A three-parameter kinetic equation describing the regularities of development of non-through-thickness fatigue cracks in the studied steels is proposed, and its crack resistance parameters are determined. The fatigue life values calculated on the basis of the derived equation are compared with the experimental data.
Keywords: high-alloyed steels, cyclic crack resistance, fatigue life, stress intensity factor, coefficient of stress cycle asymmetry, semi-elliptical crack
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