Original paper
Grain-boundary morphology and crystallography in recrystallized hornblende
Cumbest, Randolph J.
European Journal of Mineralogy Volume 3 Number 3 (1991), p. 549 - 558
27 references
published: Jun 5, 1991
manuscript accepted: Jan 29, 1991
manuscript received: Oct 16, 1990
DOI: 10.1127/ejm/3/3/0549
Abstract
Abstract Transmission electron microscopy of intraphase grain-boundaries in hornblende between new intragranular grains and their enclosing host reveals diverse morphologies ranging from long, extremely straight featureless boundaries to boundaries with cuspate and asymmetrical step - like protrusions. In almost all cases changes in grain-boundary orientation are marked by an intersecting dislocation array in the host-grain lattice. Measurements of orientation relationships between intragranular grains and their hosts indicate that the recrystallized grain-boundary orientations show a tendency to be parallel to {110}, (010), (100) and {011} of their hosts, suggesting control on the boundary orientations by the host lattice. However, detailed examination of the grain boundaries shows no periodic grain-boundary structures. Intragranular grain growth in these samples has been inferred from other studies to have been mainly accommodated by grain-boundary migration. The morphologies of the intraphase grain-boundaries are interpreted to be grain-boundary migration features.
Keywords
grain-boundary morphology • grain-boundary migration • amphibole • hornblende