PSI - Issue 13

V.N. Shlyannikov et al. / Procedia Structural Integrity 13 (2018) 1117–1122 Boychenko N.V. / Structural Integrity Procedia 00 (2018) 000 – 000

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Conclusions Cruciform specimens of two configurations and a compact tension – shear specimen subjected to mixed Mode I/II loading were used to study the crack-tip nonlinear fracture resistance parameters by using an elastic – plastic FE analysis. The investigated materials were two types of steel and titanium and aluminium alloys. For the given geometry of the specimen analyzed, the governing parameter of the elastic – plastic crack-tip stress field I n -integral, the stress triaxiality parameter, and the J-integral were determined as a function of mode mixity and elastic – plastic material properties. The numerical results for the specimen geometries considered indicated coupling between mode mixity and material nonlinearity. The significant effect of elastic-plastic material properties, described by strain hardening exponent, on the J-integral is observed in the full range of mode mixity. G.C. Sih, 1974. Handbook of stress-intensity factors vol 2., Bethlehem: Lehigh Univ. Press, 406 J.D. Lee, H. Liebowitz, 1977. The nonlinear and biaxial effects on energy release rate, J-integral and stress intensity factor. Engineering Fracture Mechanics, 9, 765-779. B.S. Henry, A.R. Luxmoore, 1997. The stress triaxiality constraint and the Q-value as ductile fracture parameter. 55, 375-390. V.N. Shlyannikov, A.V. Tumanov. 2014. Characterization of crack tip stress fields in test specimens using mode mixity parameters. International journal of fracture 123, 49 – 76. H. Richard, B. Schramm, N. Schirmeisen, 2014. Cracks on mixed mode loadingtheories, experiments, simulations. International journal of fatigue, 62, 93-103. M.R. Ayatollahi, B. Saboori, 2015. T-stress effects in mixed mode I/II/III brittle fracture. Engineering Fracture Mechanics, 144, 32-45. V.N. Shlyannikov, A.P. Zakharov. 2017. Generalization of mixed mode crack behaviour by the plastic stress intensity factor. Theoretical and applied fracture mechanics, 91, 52-65. References