Experimental and Numerical Evaluation of In-plane Tensile Mode Stress Intensity Factor for Edge Crack Using Empirical Formulation of Displacement Extrapolation Method

This paper presents a comprehensive study on fracture mechanics, with a focus on stress intensity factor (SIF) determination, using a combination of experimental, numerical, and empirical methods. The investigation focuses on the creation of an improved finite element model using the AL2014 alloy, which is commonly used in aerospace and structural engineering. Compact tension (CT) specimens of AL2014 were subjected to fatigue pre-cracking in accordance with ASTM E399 guidelines. The study proposes an empirically modified displacement extrapolation technique for accurate SIF calculation that takes pre-crack conditions into account. The experimental results were used to validate ANSYS numerical simulations. The proposed empirical displacement extrapolation method outperformed traditional finite element analysis and displacement extrapolation in terms of accuracy. For example, the stress intensity factor (K_Q) for Sample 1 was determined experimentally as 28.873 MPam0.5, numerically as 30.44 MPam0.5, and empirically as 29.01 MPam0.5, demonstrating the precision of the new approach. The results demonstrate the empirical equation's ability to predict stress intensity factors with high precision when both initial crack length and pre-crack conditions are taken into account. In terms of accuracy and applicability, the proposed method outperforms traditional approaches, with promising implications for fracture mechanics analysis.