Effect of cold working and isochronal annealing processing parameters on special grain boundary fractions in commercial purity nickel

The focus of the present study was to study the effects of cold rolling and isochronal annealing processing parameters on both the fraction of special boundaries and the random boundary connectivity in commercially pure nickel. Secondary objectives were to determine which processing schedules were most effective at increasing Fsp and disrupting the random boundary connectivity.;Commercially pure nickel was chosen for this study since alloying elements play important roles in the resulting strain distributions after deformation as well as the grain boundary movement during subsequent annealing.;To study the interacting effects of processing on microstructural characteristics, the following three variables were chosen, while holding all others constant: (1) Percent reduction in thickness by cold rolling; (2) Annealing temperature; (3) Number of cycles of sequential cold rolling and annealing.;It was found that one cycle of 5% strain by cold rolling, followed by annealing at 900°C for 10 minutes produced the highest increase in Fsp from the as-received fraction of 35% to 65%. (Abstract shortened by UMI.).