Steel Alloy Hot Roll Simulations and Through-Thickness Variation Using Dislocation Density-Based Modeling

Rensburg, Gerhardus J Jansen van; Kok, Schalk; Wilke, Daniel N.

doi:10.1007/s11663-017-1024-7

Cited by 4 publications

(7 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Once the next volume fraction is solved at t + δt, the residuals on the two ISV estimates can be determined using the evolution rates of Eqs. (28) and (29). This…”

Section: Discussionmentioning

confidence: 75%

“…• The average slip plane lattice incompatibility is aected by a constant that can be calibrated in both Eqs. (25) and (28) where it plays a role and so the evolution of λ according to Eq. (29) is simply modelled using C λ = 1.…”

Section: Internal State Variable Evolutionmentioning

confidence: 99%

mentioning

confidence: 99%

“…Our primary application of interest is to simulate industrial metal forming processes such as hot rolling [28]. for alloys with multiple phases that is hot worked [17] or linked to additional evolution equations to model recrystallisation kinetics [8,19,27,28,48]. A continuum or mean eld modelling approach to recrystallisation could further have critical recrystallisation criteria that depend explicitly on strain, strain rate or another critical value of stored energy [3,42,45].…”

mentioning

confidence: 99%

See 3 more Smart Citations

Modelling multiple cycles of static and dynamic recrystallisation using a fully implicit isotropic material model based on dislocation density

2018

View full text Add to dashboard Cite

This paper presents the development and numerical implementation of a state variable based thermomechanical material model, intended for use within a fully implicit nite element formulation. Plastic hardening, thermal recovery and multiple cycles of recrystallisation can be tracked for single peak as well as multiple peak recrystallisation response. The numerical implementation of the state variable model extends on a J 2 isotropic hypo-elastoplastic modelling framework. The complete numerical implementation is presented as an Abaqus UMAT and linked subroutines. Implementation is discussed with detailed explanation of the derivation and use of various sensitivities, internal state variable management and multiple recrystallisation cycle contributions. A ow chart explaining the proposed numerical implementation is provided as well as verication on the convergence of the material subroutine. The material model is characterised using two high temperature data sets for Cobalt and Copper. The results of Finite Element Analyses using the material parameter values characterised on the Copper data set are also presented.

show abstract

“…Once the next volume fraction is solved at t + δt, the residuals on the two ISV estimates can be determined using the evolution rates of Eqs. (28) and (29). This…”

Section: Discussionmentioning

confidence: 75%

Section: Internal State Variable Evolutionmentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Modelling multiple cycles of static and dynamic recrystallisation using a fully implicit isotropic material model based on dislocation density

2018

View full text Add to dashboard Cite

show abstract

“…Bruhns and Anding (1999) eectively illustrated this using a least squares criterion for dierent model formulations and optimization methods. This is also useful for complex material models where a uniform distribution in stresses may be assumed as an initial or rst order estimate of material properties (Jansen van Rensburg , 2016;Jansen van Rensburg et al, 2017).…”

Section: Introductionmentioning

confidence: 99%

Simultaneous estimation of boundary conditions and material model parameters

Rensburg

Kok

Wilke

2018

Struct Multidisc Optim

View full text Add to dashboard Cite

Room temperature experimental compression test data is available for dierent hardmetals. This data indicates the presence of some spatial inhomogeneity due to a compression instability, eccentric loading or time varying equivalent bending moment. To account for this, an inverse analysis is employed that determines not only the constitutive material model parameter values but also the displacement boundary conditions that best replicate the experimental data. The unknown boundary displacement history is approached using a systematically rened piecewise linear approximation, determined alongside material parameter values. The systematic simultaneous estimation of material parameter values and boundary approximations is also investigated using a virtual problem for which the exact solution is known. This investigation conrms that known material parameter values and boundary conditions can be recovered without using any prior knowledge of the exact displacement boundary conditions.

show abstract

Modeling Microstructure Evolution in a Martensitic Stainless Steel Subjected to Hot Working Using a Physically Based Model

Safara

Engberg

Ågren

2018

Metall Mater Trans A

View full text Add to dashboard Cite

The microstructure evolution of a martensitic Stainless steel subjected to hot compression is simulated with a physically based model. The model is based on coupled sets of evolution equations for dislocations, vacancies, recrystallization, and grain growth. The advantage of this model is that with only a few experiments, the material-dependent parameters of the model can be calibrated and used for a new alloy in any deformation condition. The experimental data of this work are obtained from a series of hot compression, and subsequent stress relaxation tests performed in a Gleeble thermo-mechanical simulator. These tests are carried out at various temperatures ranging from 900 to 1200°C, strains up to 0.7, and strain rates of 0.01, 1, and 10 s À1. The grain growth, flow stress, and stress relaxations are simulated by finding reasonable values for model parameters. The flow stress data obtained at the strain rate of 10 s À1 were used to calibrate the model parameters and the predictions of the model for the lower strain rates were quite satisfactory. An assumption in the model is that the structure of second phase particles does not change during the short time of deformation. The results show a satisfactory agreement between the experimental data and simulated flow stress, as well as less than 5 pct difference for grain growth simulations and predicting the dominant softening mechanisms during stress relaxation according to the strain rates and temperatures under deformation.

show abstract

Steel Alloy Hot Roll Simulations and Through-Thickness Variation Using Dislocation Density-Based Modeling

Cited by 4 publications

References 32 publications

Modelling multiple cycles of static and dynamic recrystallisation using a fully implicit isotropic material model based on dislocation density

Modelling multiple cycles of static and dynamic recrystallisation using a fully implicit isotropic material model based on dislocation density

Simultaneous estimation of boundary conditions and material model parameters

Modeling Microstructure Evolution in a Martensitic Stainless Steel Subjected to Hot Working Using a Physically Based Model

Contact Info

Product

Resources

About