Finite element analysis of extruded AA6061-T6 mechanical connection in low-cycle fatigue
Item TypeGraduate Thesis
CommitteeRushing, Timothy, W.
Priddy, Matthew, W.
The low-cycle fatigue (LCF) life of the extruded aluminum alloy 6061-T6 (AA6061-T6) AM2 matting connection system was analyzed through 3D finite element modeling in conjunction with the plasticity-damage (DMG) and multi-stage fatigue (MSF) material models. The connection was modeled in ABAQUS Explicit based on the real-world boundary conditions of AM2 matting. The DMG-MSF user-defined material model characterized the low-cycle fatigue damage evolution within the microstructure of the extruded AA6061-T6 connection and utilized the maximum effective strain amplitude to predict the life of each stage of the fatigue process. It was determined that a constant displacement range of 15.17 mm generated an effective strain amplitude of 6.8E-03 mm/mm and a predicted total fatigue life within 1% to the laboratory- and full-scale data at approximately 1,122 cycles. The LCF characterization of the connection system allows for a significant reduction in laboratory- and full-scale testing for future design improvements.