Fracture Evaluation and Design Tool for Welded Aluminum Ship Structures Subjected to Impulsive Dynamic Loading

Aluminum as a structural material for naval applications has a number of advantages over steel, owing mainly to significant weight reductions which translate to higher speed and range attainable by aluminum vessels. A comprehensive study of research needs for aluminum structures identified the key research areas, which included material behavior and fracture evaluation of welded aluminum structures subjected to dynamic loading. In order to meet the Navy"s needs for high speed aluminum vessels, a new, accurate and efficient fracture evaluation methodology for welded and unwelded aluminum components is proposed. The new constitutive model will be formulated in the context of ductile fracture mechanics and will account for anisotropic, nonlinear and rate dependent behavior of aluminum sheets. After validation, the constitutive model will be used to develop a fast assessment tool for evaluation of ultimate strength of ship components, as well as accurate and efficient estimates of the operational recoverability of the aluminum ships subjected to extreme events. Efficient and accurate fracture evaluation methodology, as well as the fast assessment tool allowing for both detailed simulation of the fracture process and fast assessment of ultimate strength of aluminum ship components could lead to great savings in military and commercial applications.