  The main aim of the present work is to estimate the effective elastic
stiffnesses of a two-phase diamond/$\beta$-SiC composite thin film that is
fabricated by chemical vapor deposition. The parameters of linear elasticity
are determined by numerical homogenization. The database is sparse since for
the 3D volume of interest only two micrographs displaying the phase
distributions in perpendicular planes are available; micrographs each of a
cross-section and the surface of the thin film. A representative volume element
(RVE) is reconstructed by an optimization software and by means of identified
material symmetries in 2D of the specimen. The elastic homogenization results
indicate that the two-phase diamond/$\beta$-SiC composite exhibits the behavior
of transverse isotropy, for which the set of six independent material
parameters is identified.
