The influence of the first non-singular stress terms on crack initiation direction in an orthotropic bi-material plate

0435374 - ÚFM 2015 RIV NL eng J - Journal Article
Klusák, Jan - Hrstka, M. - Profant, T. - Krepl, Ondřej - Ševeček, O. - Kotoul, M.
The influence of the first non-singular stress terms on crack initiation direction in an orthotropic bi-material plate.
Theoretical and Applied Fracture Mechanics. Roč. 71, JUN (2014), s. 67-75. ISSN 0167-8442. E-ISSN 1872-7638
R&D Projects: GA MŠMT(CZ) ED1.1.00/02.0068; GA ČR GA14-11234S
Institutional support: RVO:68081723
Keywords : Bi-material notch * Crack initiation direction * Non-singular stress term * Generalized fracture mechanics * Path-independent integral
Subject RIV: JL - Materials Fatigue, Friction Mechanics
Impact factor: 1.262, year: 2014

A bi-material free edge singularity composed of two orthotropic parts is considered as a bi-material notch with ω1=ω2=90° under general loading. Besides the singular term the first non-singular term is also included in the stress distribution at the notch tip. The Stroh-Eshelby-Lekhnitskii formalism for plane elasticity is used to express stress and displacement fields and the strain energy density factor. The exponents of the singular and non-singular stress terms and corresponding eigenvectors are the solution of the eigenvalue problem resulting from the prescribed boundary and compatibility conditions prevailing at the notch tip. The potential direction of crack initiation is determined from the local minimum of the mean value of the strain energy density factor in both materials. The necessary knowledge of the generalized stress intensity factor and generalized T-stress is realized by means of the employment of the two state conservation integrals. Following the assumption of the same mechanism of rupture in the case of a crack and a notch, an expression for the critical values of the generalized stress intensity factor is obtained.
Permanent Link: http://hdl.handle.net/11104/0239280