Finite Element Modeling of Crack Initiation Angle Under Mixed Mode (I/II) Fracture

Subject Areas : Engineering

S.S Bhadauria ¹ , K.K Pathak ² , M.S Hora ³

1 - Department of Applied Mechanics, Maulana Azad National Institute of Technology Bhopal
2 - Advanced Materials Processes Research Institute (CSIR)
3 - Department of Applied Mechanics, Maulana Azad National Institute of Technology Bhopal

Received: 2010-06-08 Accepted : 2010-09-16 Published : 2010-09-30

Keywords: Finite Element Method, Stress intensity factor, Mixed mode fracture, J-integral, Crack initiation angle, Fracture criteria,

Abstract :

Present study deals with the prediction of crack initiation angle for mixed mode (I/II) fracture using finite element techniques and J-Integral based approach. The FE code ANSYS is used to estimate the stress intensity factor numerically. The estimated values of SIF were incorporated into six different crack initiation angle criteria to predict the crack initiation angle. Single edge crack specimens of Araldite-Hardener were used for the present analysis. Load was applied up to critical limit of the specimens containing crack at different angles of inclination. The crack initiation angle obtained using stress intensity factor and J-integral based approach were found close to each other and also found to be in good agreement with the available experimental results in literature. It is also investigated that as crack inclination angle increases material was found to behave in a brittle manner.

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