Molokov K.A.

KONSTANTIN A. MOLOKOV, Ph.D., Assistant Professor, Department of Welding Engineering, School of Engineering, Far Eastern Federal University, Vladivostok. 8 Sukhanova St., Vladivostok, Russia, 690950, e-mail: spektrum011277@gmail.com

Some aspects of the formation of the contour of surface cracks

Characteristic of the welded joints in metal structures is the variation in the size of the grain of ferritic-pearlitic steels and the presence of various concentrators provoking the appearance of fatigue cracks. The article presents the dependences established by the author, which make it possible to assess the effect of various properties of the material, the diameter of grain, and the stresses on the shape of surface cracks. Demonstrated is the dependence of the ratios of stress intensity factors calculated by the author for different stresses on Poisson's ratio.

Key words: welded structure, welding defect, stress concentrator, strength, fatigue crack, flaw shape.

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