  Materials with an allotropic phase transformation can result in the formation
of microstructures where grains have orientation relationships (ORs) determined
by the transformation history. These microstructures influence the final
material properties. In zirconium alloys, there is a solid-state body centred
cubic (BCC) to hexagonal close packed (HCP) phase transformation, where the
crystal orientations of the HCP phase can be related to the parent BCC
structure via the Burgers orientation relationship (BOR). In the present work,
we adapt a reconstruction code developed for steels which uses a Markov Chain
clustering algorithm to analyse electron backscatter diffraction (EBSD) maps
and apply this to the HCP and BCC BOR. This algorithm is released as
open-source code (via github, as ParentBOR). The algorithm enables new post
processing of the original and reconstructed data set to analyse the variants
of the HCP alpha-phase that are present and understand shared crystal planes
and shared lattice directions within each parent beta grain, and we anticipate
that this assists in understanding the transformation related deformation
properties of the final microstructure. Finally, we compare the ParentBOR code
with recently released reconstruction codes implemented in MTEX to reveal
differences and similarities in how the microstructure is described.
