Energy response of S355 and 41Cr4 steel during fatigue crack growth process

• Type: Article in International Scientific Journal
• Date: 2018

Authors

G. Lesiuk (Author) Other; M. Szata (Author) Other; D. Rozumek (Author) Other; Z. Marciniak (Author) Other; José Correia (Author) FEUP; Abílio M. P. de Jesus (Author) FEUP

Journal

Title: Journal of Strain Analysis for Engineering Design

Vol. 53 No. 8

Pages: 663-675

ISSN: 0309-3247

Publisher: SAGE

Indexing

ISI Web of Knowledge - 5 Citations

Scopus - 20 Citations

INSPEC

Other information

Authenticus ID: P-00P-Y9W

DOI: 10.1177/0309324718798234

Abstract (EN): In this research, a novel approach of the fatigue crack growth rate description has been proposed. Based on theoretical and experimental approach, the mean stress effect expressed by R-ratio is present in classical da/dN-Delta K diagram. According to energy approach - based on the irrevocably dissipated energy accumulated in material (hysteresis loop) during fatigue process - the mean stress effect can be minimalized. Experimental validation of the proposed model was performed using results of fatigue crack propagation data for S355 and 41Cr4 steels in terms of strain energy density parameter Delta S or cyclic J-integral range -Delta J. In contrast to the force approach based on K-max (or Delta K), the energy parameters Delta S or Delta J represent unambiguously the fatigue crack propagation rate, without influence of mean stress effect -R-ratio. However, in near threshold range of kinetic fatigue fracture diagram, the energy parameter displays a slight dispersion of the experimental data. According to the crack closure theory and its U-Elber parameter, the dispersion of experimental data is decreased. Therefore, the crack closure effects have a high significance in energy model - similar to the 'force approach' based on Delta K concept.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 13