  Characterizing the spacing of primary dendrite arms in
directionally-solidified microstructures is an important step for developing
process-structure-property relationships by enabling the quantification of (i)
the influence of processing on microstructure and (ii) the influence of
microstructure on properties. In this work, we utilized a new Voronoi-based
approach for spatial point pattern analysis that was applied to an experimental
dendritic microstructure. This technique utilizes a Voronoi tessellation of
space surrounding the dendrite cores to determine nearest neighbors and the
local primary dendrite arm spacing. In addition, we compared this technique to
a recent distance-based technique and a modification to this using Voronoi
tesselations. Moreover, a convex hull-based technique was used to include edge
effects for such techniques, which can be important for thin specimens. These
methods were used to quantify the distribution of local primary dendrite arm
spacings, their spatial distribution, and their correlation with interdendritic
eutectic particles for an experimental directionally-solidified Ni-based
superalloy micrograph. This can be an important step for correlating with both
processing and properties in directionally-solidified dendritic
microstructures.
