Three-dimensional (3D) grain sizes and size distribution functions
(SDFs) are generally obtained by converting the 2D or ID grain sizes to 3D
with the methods based on a spherical grain shape model (S-model), which
can produce large systematic errors. In this report, a new polyhedral
grain model (P-model) is developed and experimentally checked with the
directly measured 3D grain sizes. The results show that the systematic
error originating from the S-model can be corrected by using the new
polyhedral grain model.
