Orientation Imaging Microscopy (OIM) methods were applied to the analysis of the microstructure and microtexture as well as the deformation and failure modes of superplastic AA5083 aluminum alloys. Annealing of a cold-rolled AA5083 material at 450Ã°C resulted in the formation of equiaxed grains approximately 7Ã¦m - 8Ã¦m in size. Random grain-to-grain misorientations were consistent with particle-stimulated nucleation of recrystallization during processing for superplasticity. Such a microstructure is necessary for superplasticity but mechanical property data indicated only moderate ductility and failure by cavity formation and linkage. This investigation then employed OIM methods to identify the misorientations of boundaries prone to cavitation and determine the role of such boundaries in failure of these materials during elevated temperature deformation.
McNelley, Terry R.
Naval Postgraduate School (U.S.)
Naval Postgraduate School
M.S. in Mechanical Engineering
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