9612343 Doherty The process of plastic deformation is explored at the level of individual grains in a polycrystalline metal the related nature of the interactions between adjacent grains. To this end the evolution of grain-scale microstructure occurring with deformation in commercially pure aluminum is studied using a Osplit sample testO in channel-die compression. Back-scattered Kikuchi diffraction (BKD) and Orientation Imaging Microscopy (OIM) are employed to determine grain orientations. A selected range of deformation paths, strain levels, temperatures and strain rates, grain sizes, sub- grain particles, and starting textures are explored to gain understanding of the deformation process. A goal of the research is to determine the inherent length scale that is associated with in-grain misorientations; this is the size of the regions which rotate together within each grain. Local strain distribution is measured within and between grains using photoresist techniques and OIM. Modeling is aimed at correcting observed deficiencies in current models and are extended for the prediction of the observed inherent length scales. %%% The plastic deformation of polycrystalline metallic alloys is an important process in wrought alloy manufacture. The research could lead to a predictive model for in-grain misorientations and recrystallization. ***
