Influence of Notch Depth-to-Width Ratios on J-Integral and Critical Failure Load of Single-Edge Notched Tensile Aluminium 8011 Alloy Specimens

Subject Areas : Engineering

C.S Sumesh ¹ , P.J Arun Narayanan ²

1 - Department of Mechanical Engineering, Amrita School of Engineering, Coimbatore Amrita Vishwa Vidyapeetham, India
2 - Department of Mechanical Engineering, Amrita School of Engineering, Coimbatore Amrita Vishwa Vidyapeetham, India

Received: 2017-09-19 Accepted : 2017-12-13 Published : 2018-03-01

Keywords: J-integral, fracture toughness, Aluminium 8011 alloy, Notch depth, Critical failure load,

Abstract :

In this paper, the influence of notch depth-to-width ratios on J-integral and critical load of Aluminium 8011 alloy specimens with U-notch under Mode I loading are studied. Using experiments, for a set of specimens having different notch depth–to–width ratios, J-integral was found and the same was verified using analytical methods. Further, using the results obtained from the experiments, failure assessment diagrams (FAD) were plotted for the same ratios, to determine the safe or critical load and the type of failure mechanism was also studied. The results show that, for both shallow and deep notch depths, the J-integral values obtained from the experimental method, are in very close agreement with the analytical values. J-integral values decrease with increase in notch depth and increase with increase in applied load. Furthermore, from FAD, the safe load decreases when the notch depth-to-width ratio increases and it was found that, all the tested specimens failed due to elastic plastic deformation mechanism.

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