A phase field model incorporating strain gradient viscoplasticity: Application to rafting in Ni-base superalloys

Cottura, Maeva; Bouar, Y. Le; Finel, A.; Appolaire, Benoît; Ammar, Kais; Forest, Samuel

doi:10.1016/j.jmps.2012.04.003

Cited by 81 publications

(43 citation statements)

References 47 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…M evolution with dislocations located at the moving phase interface have been treated by Kundin et al (2011a). PFA solutions for martensitic PT with continuum dislocation theory are presented in Kundin et al (2011b) and with macroscopic von Mises plasticity in Cottura et al (2012); Yeddu et al (2012a); Malik et al (2012); Yamanaka et al (2008).…”

Section: Introductionmentioning

confidence: 99%

Interaction between phase transformations and dislocations at the nanoscale. Part 2: Phase field simulation examples

Javanbakht

Levitas

2015

Journal of the Mechanics and Physics of Solids

View full text Add to dashboard Cite

The complete system of phase field equations for coupled martensitic phase transformations (PTs), dislocation evolution, and mechanics at large strains is presented. Finite element method (FEM) is utilized to solve this system for two important problems. The first one is related to the simulation of shear strain-induced PT at the evolving dislocation pile-ups in a nanosized bicrystal. Plasticity plays a dual part in the interaction with PT. Dislocation pile-ups produce strong stress tensor concentrators that lead to barrierless martensite (M) nucleation. On the other hand, plasticity in the transforming grain relaxes these stress concentrators suppressing PT. The final stationary M morphology is governed by the local thermodynamic equilibrium, either at the interfaces or in terms of stresses averaged over the martensitic region or the entire grain. This is very surprising because of strong heterogeneity of stress fields and is in contrast to previous statements that phase equilibrium conditions do not enter the description of strain-induced PTs. The second problem is devoted to martensitic plate propagation through a bicrystal during temperature-induced PT. For elastic growth (without dislocations) and a large thermal driving force, a complex transformation path with plate branching and direct and reverse PTs is observed, which still ends with the same stationary nanostructure as for a smaller driving force and a traditional transformation path. Sharp grain boundary arrests plate growth at a relatively small driving force, exhibiting an athermal friction. For elastoplastic growth, the generation of dislocations produces athermal friction and arrests the plate below some critical driving force, leading to a morphological transition from plate to lath M. The width of the martensitic plate increases in comparison with elastic growth * Corresponding author. Email address: vlevitas@iastate.edu, tel. (515)-294-9691 (V. I. Levitas) 2 due to internal stress relaxation. Plate growth is accompanied by the nucleation of dislocations within M and remaining in M, the nucleation of dislocations at the tip of a plate and spreading them in austenite (A), and passing some dislocations through M, then through a M-A interface, and then through A. Due to the existence of a stationary equilibrium M nanostructure and concentration for each temperature, for a large enough observation time one observes athermal, rate-and time-independent kinetics, even while local kinetics is rate dependent. In the final structure, most dislocations are in M despite its having a yield strength three times larger than for A, which is consistent with experiments.

show abstract

Section: Introductionmentioning

confidence: 99%

Interaction between phase transformations and dislocations at the nanoscale. Part 2: Phase field simulation examples

Javanbakht

Levitas

2015

Journal of the Mechanics and Physics of Solids

View full text Add to dashboard Cite

show abstract

“…209 and an application in 210 ), or on a small time and space scale of a physical process. This is the case for example of phase field modelling incorporating crystal plasticity 211,212 . But having phase field coupled to crystal plasticity, would it be by FE or not, in order to achieve a comprehensive description of deformation combined to phase transformation or recrystallisation involved in the process of elaboration of a metal alloy RVE remains a very high challenge.…”

Section: General Discussion and Future Developmentsmentioning

confidence: 99%

Modelling Polycrystalline Materials: An Overview of Three-Dimensional Grain-Scale Mechanical Models

Benedetti

Barbe

2013

J. Multiscale Modelling

View full text Add to dashboard Cite

A survey of recent contributions on three-dimensional grain-scale mechanical modelling of polycrystalline materials is given in this work. The analysis of material microstructures requires the generation of reliable micro-morphologies and affordable computational meshes as well as the description of the mechanical behavior of the elementary constituents and their interactions. The polycrystalline microstructure is characterized by the topology, morphology and crystallographic orientations of the individual grains and by the grain interfaces and microstructural defects, within the bulk grains and at the inter-granular interfaces. Their analysis has been until recently restricted to twodimensional cases, due to high computational requirements. In the last decade, however, the wider affordability of increased computational capability has promoted the development of fully three-dimensional models. In this work, different aspects involved in the grain-scale analysis of polycrystalline materials are considered. Different techniques for generating artificial micro-structures, ranging from highly idealized to experimentally based high-fidelity representations, are briefly reviewed. Structured and unstructured meshes are discussed. The main strategies for constitutive modelling of individual bulk grains and inter-granular interfaces are introduced. Some attention has also been devoted to three-dimensional multiscale approaches and some established and emerging applications have been discussed.

show abstract

“…Similar approaches including isotropic plasticity models have been developed in [21,22,23,24,25]. In the context of rafting in Ni-based superalloys, a few works have extended the PFM to include strain gradient plasticity [26] and anisotropic plasticity, either approximately [27] or relying on a more complete and well tested crystal plasticity framework [28]. Despite some valuable achievements, for calibrating their parameters the phenomenological laws used in these models require experiments that are unfortunately more complex than usual when considering evolving multi-phase materials.…”

Section: Introductionmentioning

confidence: 99%

“…First, it is important to account properly for the forest hardening due to the short-range interactions between dislocations, as shown in [29]. Second, at the micrometer scale, the hardening associated with the confinement of the plastic domains can be significant, and likely to change during microstructural evolutions [26]. Thus, it is also mandatory to account for this effect in the same consistent framework, such as in [30].…”

Section: Introductionmentioning

confidence: 99%

Coupling the Phase Field Method for diffusive transformations with dislocation density-based crystal plasticity: Application to Ni-based superalloys

Cottura

Appolaire

Finel

et al. 2016

Journal of the Mechanics and Physics of Solids

Self Cite

View full text Add to dashboard Cite

A phase field model incorporating strain gradient viscoplasticity: Application to rafting in Ni-base superalloys

Cited by 81 publications

References 47 publications

Interaction between phase transformations and dislocations at the nanoscale. Part 2: Phase field simulation examples

Interaction between phase transformations and dislocations at the nanoscale. Part 2: Phase field simulation examples

Modelling Polycrystalline Materials: An Overview of Three-Dimensional Grain-Scale Mechanical Models

Coupling the Phase Field Method for diffusive transformations with dislocation density-based crystal plasticity: Application to Ni-based superalloys

Contact Info

Product

Resources

About