Finite Element Modeling of Crack Tip Blunting for Estimation of Energy Release Rate Component of Mode I Crack near a Strength Mismatched Interface

Sunil Bhat, Vijay G. Ukadgaonker

Department of Mechanical Engineering, Indian Institute of Technology, Mumbai, India.
School of Mechanical and Building Sciences, VIT University, Vellore, India.

DOI: 10.4236/am.2013.45A001                

Abstract

The paper presents finite element modeling of crack tip blunting for numerical estimation of fracture parameter of a Mode I crack, in weak alloy steel, which is near and normal to the interface of elastically identical but stronger maraging steel. The bimetallic body is subjected to monotonic load in K dominated regime. Crack tip yield zone across the interface, treated as Dugdale’s cohesive zone, is isolated from the bimetallic domain and is modeled alone under the action of respective cohesive stress over yield zones for obtaining the contribution of mismatch between yield strength of the steels in crack energy release rate component, J_interface. Effect of far field load on J_interface is found separately from a theoretical model. Numerical and theoretical results of J_interface are in good agreement.

Keywords

Crack Tip Blunting; Interface; J Integral; Strength Mismatch; Mode I Crack

Conflicts of Interest

The authors declare no conflicts of interest.

References

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