Abstract
An understanding of load sharing among constituent phases aids in designing mechanical properties
of multiphase materials. Here we investigate load partitioning between the body-centered-cubic iron
matrix and NiAl-type precipitates in a ferritic alloy during uniaxial tensile tests at 364 and 506 °C on
multiple length scales by in situ neutron diffraction and crystal plasticity finite element modeling.
Our findings show that the macroscopic load-transfer efficiency is not as high as that predicted by
the Eshelby model; moreover, it depends on the matrix strain-hardening behavior. We explain the
grain-level anisotropic load-partitioning behavior by considering the plastic anisotropy of the matrix
and elastic anisotropy of precipitates. We further demonstrate that the partitioned load on NiAl-type
precipitates relaxes at 506 °C, most likely through thermally-activated dislocation rearrangement
on the microscopic scale. The study contributes to further understanding of load-partitioning
characteristics in multiphase materials.
