A Three Dimensional Discrete Dislocation Dynamics Analysis of Cyclic Straining in 316L Stainless Steel

Christophe Déprés; Christian F. Robertson; Marc Fivel; Suzanne Degallaix

doi:10.4028/www.scientific.net/MSF.482.163

Paper Titles

Effect of Ordering on the Elastic Parameters of Multicomponent Ni-Based Systems
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Near-Field Study of Carrier Dynamics in InAs/GaAs Quantum Dots Grown on InGaAs Layers
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Disorientations and Their Role on the Work-Hardening in Stage IV
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Stability and Motion of Low Angle Dislocation Boundaries in Precipitation Hardened Crystals
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A Three Dimensional Discrete Dislocation Dynamics Analysis of Cyclic Straining in 316L Stainless Steel
p.163

The Migration of Solute Atoms in the Stress Field of a Slowly Moving Crack
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Modelling Cleavage Fracture in High Strength Steels and Their Welds
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Micromechanisms of Cleavage Fracture in HAZ of Low Carbon Steel Welds
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Dislocation Structures of Duplex Stainless Steel in Uniaxial and Biaxial Cyclic Loading
p.179

HomeMaterials Science ForumMaterials Science Forum Vol. 482A Three Dimensional Discrete Dislocation Dynamics...

A Three Dimensional Discrete Dislocation Dynamics Analysis of Cyclic Straining in 316L Stainless Steel

Abstract:

The early stages of the formation of dislocation microstructures in low strain fatigue are analysed,using three-dimensional discrete dislocation dynamics modelling (DDD). A detailed analysis of the simulated microstructures provide a detailed scheme for the persistent slip band formation, emphasizing the crucial role of cross-slip for both the initial strain spreading inside of the grain and for the subsequent strain localization in the form of slip bands. A new ad-hoc posttreatment tool evaluates the surface roughness as the cycles proceed. Slip markings and their evolutions are analysed, in relation to the dislocation microstructure. This dislocation-based study emphasizes the separate contribution of plastic slip in damage nucleation. A simple 1D dislocation based model for work-hardening in crystal plasticity is proposed. In this model, the forest dislocations are responsible for friction stress (isotropic work-hardening), while dislocation pile-ups and dislocation trapped in Persistent Slip Bands (PSB) produce the back stress (kinematic workhardening). The model is consistent with the stress-strain curves obtained in DDD. It is also consistent with the stress-strain curves experimentally obtained for larger imposed strain amplitudes.