  Selective laser melting is receiving increasing interest as an additive
manufacturing technique. Residual stresses induced by the large temperature
gradients and inhomogeneous cooling process can favour the generation of
cracks. In this work, a crystal plasticity finite element model is developed to
simulate the formation of residual stresses and to understand the correlation
between plastic deformation, grain orientation and residual stresses in the
additive manufacturing process. The temperature profile and grain structure
from thermal-fluid flow and grain growth simulations are implemented into the
crystal plasticity model. An element elimination and reactivation method is
proposed to model the melting and solidification and to reinitialise state
variables, such as the plastic deformation, in the reactivated elements. The
accuracy of this method is judged against previous method based on the
stiffness degradation of liquid regions by comparing the plastic deformation as
a function of time induced by thermal stresses. The method is used to
investigate residual stresses parallel and perpendicular to the laser scan
direction, and the correlation with the maximum Schmid factor of the grains
along those directions. The magnitude of the residual stress can be predicted
as a function of the depth, grain orientation and position with respect to the
molten pool.
