Perpustakaan Digital ITB

Aluminum alloys are widely used in aerospace, automotive, and construction industries due to their strength and lightweight properties. However, welding introduces residual stresses that can undermine the structural integrity and lifespan of welded components. This study investigates the effects of these residual stresses on crack behavior in aluminum welded joints, extending the traditional J-integral framework, where originally developed for linear elastic fracture mechanics to fully plastic conditions using the EPRI scheme. The Ramberg-Osgood plasticity model was employed to describe the material's nonlinear stress-strain behavior. The results reveal that high residual stresses from welding significantly increase the values of the Elastic-Plastic, Elastic, and Fully Plastic J-Integrals. These high stresses may push the material into plastic deformation, particularly when the stresses exceed the yield point. In contrast, materials subjected to low loads, below the yield strength and without residual stress, show little to no value of Plastic J-Integral. This research aims to understand the crack in welded joints, enabling more accurate predictions of crack growth and structural service life. By providing a deeper insight into how residual stresses influence crack behavior and plastic deformation, this work aids in developing more effective strategies to ensure the structural integrity of welded components, ultimately enhancing the safety, durability, and efficiency of critical structures. Keywords: Residual Stress, J-Integral, Crack, Ramberg-Osgood, Plasticity