Study of Variation of the J-integral and the Fracture Toughness in Blunt V-notches under Mode I Loading

Journal of Simulation and Analysis of Novel Technologies in Mechanical Engineering

مقاله 3، دوره 6، شماره 2، آذر 2013، صفحه 21-30   

نوع مقاله: Persian

نویسندگان

F. Noori-Azghad؛ H. Khademizadeh^* ؛ E. Barati

چکیده

Fracture assessment of U- and V-notches is important in mechanical engineering. One can use the J-integral as fracture parameter in order to predict the critical fracture load in notches. The critical value of the J-integral in cracks is a function of the material properties. In notches, however, the material properties as well as the notch dimensions affect this critical value (named fracture toughness). So, one should carry out a complex and time-consuming experiment in order to find the fracture toughness. In this paper, a practical equation has been derived to evaluate the critical value of the J-integral in blunt V-notches under Mode I loading. By means this new expression, only the notch dimensions and the critical value of the J-integral in cracks should be known. In this paper, the effect of the notch angle, the control volume radius to the notch root radius ratio (Rc/ρ), and the Poisson’s ratio on the J-integral and the critical value of the J-integral have been studied. Results have shown that by increasing the notch angle and the Poisson’s ratio, the fracture toughness decreases. However, the fracture toughness increases by increasing the Rc/ρ ratio. 

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