The influence of discontinuity of fracture-mechanics parameters on the failure manner of multi-material structures

0370064 - ÚFM 2012 RIV ES eng A - Abstract
Klusák, Jan - Knésl, Zdeněk - Profant, T.
The influence of discontinuity of fracture-mechanics parameters on the failure manner of multi-material structures.
Computational Modeling of Fracture and Failure of Materials and Structures. Barcelona, Spain: International Center for Numerical Mithods in Engineering, 2011 - (Oliver, X.; Jirásek, M.; Allix, O.; Moes, N.). s. 129-129. ISBN 978-84-87867-66-8.
[International Conference on of Computational Modeling of Fracture and Failure of Materials and Structures. 06.06.2011-08.06.2011, Barcelona]
R&D Projects: GA ČR GAP108/10/2049
Institutional research plan: CEZ:AV0Z20410507
Keywords : crack initiation * generalized fracture mechanics * composite materials
Subject RIV: JL - Materials Fatigue, Friction Mechanics

Within failure assessment of singular stress concentrators, the crack initiation and propagation direction is often gained from the criterion of the maximum tangential stress. But there are cases where the crack is initiated in a different direction than the direction corresponding to the global maximum of tangential stress. A case of this kind can occur during constrained crack initiation caused by discontinuity of fracture-mechanics parameters, namely the fracture toughness KIC or the threshold value KIth. An example can be the crack initiation in a multi-material wedge, where the extreme value of tangential stress occurs in one of the materials, but the crack initiates in another material part. The maximum value of tangential stress is often oriented to the material with the highest elastic module. But due to different fracture-mechanics properties (KIC or KIth) of particular materials, the crack can initiate into a material with worse fracture-mechanics properties or into the bi-material interface.
Permanent Link: http://hdl.handle.net/11104/0203975