Full-field Modelling of Crack Tip Shielding via the Plastic Inclusion Concept
This paper presents an outline of the development, verification and application of a new model of crack tip stress fields in the presence of a plastic enclave around a growing fatigue crack. The approach taken rests on capturing the effects of this plastic inclusion, comprising the crack tip and crack wake plastic zones, via elastic stress distributions applied at the elastic-plastic boundary. The model is therefore independent of the mechanisms of plastic deformation and potentially applicable to a variety of materials. A Muskhelishvili complex potential extension to the Williams crack tip stress field is found for four stress parameters representing a K-stress, a T-stress, a crack retardation stress and a compatibility-induced shear stress at the elastic-plastic boundary. This model is validated via full field fitting to photoelastic stress fringe patterns, obtained from epoxy resin and polycarbonate specimens. It has also been extended to the strain fields measured in digital image correlation techniques, which allows its application to metallic alloys.
Crack tip stresses Mathematical modeling Plastic inclusion Fracture mechanics parameters Crack shielding
M. N. James Yanwei Lu C C. J. Christopher E. A. Patterson
Faculty of Science & Technology, University of Plymouth, University UK Mechanical Engineering, Nelso Faculty of Science & Technology, University of Plymouth, University UK Composite Vehicle Research Center, Michigan State University, East Lansing, USA
国际会议
沈阳
英文
1-9
2010-07-28（万方平台首次上网日期，不代表论文的发表时间）