Mechanical response of multicrystalline thin films in mesoscale field dislocation mechanics

Plastic deformation of multicrystalline thin films: Grain size distribution vs. grain orientation

“…Numerical results obtained from a finite element implementation of MFDM are in good qualitative agreement with experimental observations and some of the key physically relevant problems has been successfully solved and documented [9,10,11]. Motivated by the experimental observations [4,5], the effect of surface passivation, grain orientation, grain boundary constraints, and film thickness on the mechanical response of multicrystalline thin films is studied using MFDM in [12]. In this study, individual grains constituting the thin film are assumed to be of equal sizes.…”

“…This is due to the accumulation of polar dislocations along grains boundaries as the misorientation between adjacent grains is high in this orientation set. This feature is discussed in detail in Puri et al [12].…”

“…However the MFDM analysis clearly demonstrates a noticeable harder response in loading. This observation comes as no surprise as conventional plasticity with no explicit characterization of dislocations is unable to account for the excess dislocation distributions which MFDM has been shown to account for accurately [9,12].…”

“…The motivation behind using the symmetric part in (6) is explained in detail in Puri et al [12]. A power law is used for…”

“…0 k is an extra parameter in the MFDM model that needs to be fitted experimentally. The boundary conditions, initial conditions and details of the numerical implementation of the equations using the Finite Element Method are described in [9,12,13].…”