TY - JOUR

T1 - Assessment of the dislocation bias in fcc metals and extrapolation to austenitic steels

AU - Chang, Zhongwen

AU - Sandberg, Nils

AU - Terentyev, Dmitry

AU - Samuelsson, C.

AU - Bonny, Giovanni

AU - Olsson, Pâr

N1 - Score=10

PY - 2015/10/3

Y1 - 2015/10/3

N2 - A systematic study of dislocation bias has been performed using a method that combines atomistic and elastic dislocation-point defect interaction models with a numerical solution of the diffusion equation with a drift term. Copper, nickel and aluminium model lattices are used in this study, covering a wide range of shear moduli and stacking fault energies. It is found that the dominant parameter for the dislocation bias in fcc metals is the width of the stacking fault ribbon. The variation in elastic constants does not strongly impact the dislocation bias value. As a result of this analysis and its extrapolation, the dislocation bias of the widely applied austenitic stainless steels of 316 type is predicted to be about 0.1 at temperature close to the swelling peak (815 K) and typical dislocation density of 1014 m2. This is in line with the bias calculated using the elastic interaction model, which implies that the prediction method can be used readily in other fcc systems even without EAM potentials. By comparing the bias values obtained using atomistic- and elastic interaction energies, about 20% discrepancy is found, therefore a more realistic bias value for the 316 type alloy is 0.08 in these conditions.

AB - A systematic study of dislocation bias has been performed using a method that combines atomistic and elastic dislocation-point defect interaction models with a numerical solution of the diffusion equation with a drift term. Copper, nickel and aluminium model lattices are used in this study, covering a wide range of shear moduli and stacking fault energies. It is found that the dominant parameter for the dislocation bias in fcc metals is the width of the stacking fault ribbon. The variation in elastic constants does not strongly impact the dislocation bias value. As a result of this analysis and its extrapolation, the dislocation bias of the widely applied austenitic stainless steels of 316 type is predicted to be about 0.1 at temperature close to the swelling peak (815 K) and typical dislocation density of 1014 m2. This is in line with the bias calculated using the elastic interaction model, which implies that the prediction method can be used readily in other fcc systems even without EAM potentials. By comparing the bias values obtained using atomistic- and elastic interaction energies, about 20% discrepancy is found, therefore a more realistic bias value for the 316 type alloy is 0.08 in these conditions.

KW - Dislocation bias

KW - Atomistic calculation

KW - Interaction energy

KW - fcc

UR - http://ecm.sckcen.be/OTCS/llisapi.dll/open/26871036

U2 - 10.1016/j.jnucmat.2015.05.042

DO - 10.1016/j.jnucmat.2015.05.042

M3 - Article

SN - 0022-3115

VL - 465

SP - 13

EP - 19

JO - Journal of Nuclear Materials

JF - Journal of Nuclear Materials

ER -