The five parameter grain boundary character distribution of α-Ti determined from three-dimensional orientation data

Commercially pure alpha-Ti was serial sectioned using a Xe plasma focused ion beam (PFIB) scanning electron microscope and orientation maps were obtained on the parallel layers by electron backscatter diffraction. The orientations and shapes of 13,900 grains and 92,100 grain faces were characterized. The mean number of faces per grain was 14.2. The grain boundaries were classified according to the three misorientation parameters and two grain boundary orientation parameters. There were more grain boundaries with 180 degrees-twist and 180 degrees-tilt character than expected in a random distribution. Furthermore, grain boundary planes with prismatic orientations were more common than those with basal orientations. The grain boundary with the greatest relative area had a 28 degrees/[0001] misorientation and (31 (4) over bar0) and (7 (25) over bar0) grain boundary planes. Compared to earlier instruments with Ga-ion sources, the milling speed of the PFIB makes it possible to collect ten times more data in a comparable time. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.