A simple, mixtures-based model for the grain size dependence of strength in nanophase metals

Carsley, John E.; Ning, Jiangli; Milligan, Walter W.; Hackney, S.A.; Aifantis, Elias C.

doi:10.1016/0965-9773(95)00257-f

Cited by 161 publications

(63 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…'grain size softening' (also called the inverse Hall-Petch relationships) [2]. A number of theories and models have been developed to understand the deviation of the strength from the empirical Hall-Petch equation [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19]. Recent molecular dynamics (MD) simulations have improved our understanding of the deformation of nanocrystalline materials [13].…”

Section: Introductionmentioning

confidence: 99%

Modeling the dependence of strength on grain sizes in nanocrystalline materials

Bhole

Chen

2008

Science and Technology of Advanced Materials

View full text Add to dashboard Cite

A model was developed to describe the grain size dependence of hardness (or strength) in nanocrystalline materials by combining the Hall-Petch relationship for larger grains with a coherent polycrystal model for nanoscale grains and introducing a log-normal distribution of grain sizes. The transition from the Hall-Petch relationship to the coherent polycrystal mechanism was shown to be a gradual process. The hardness in the nanoscale regime was observed to increase with decreasing grain boundary affected zone (or effective grain boundary thickness, ) in the form of −1/2 . The critical grain size increased linearly with increasing . The variation of the calculated hardness value with the grain size was observed to be in agreement with the experimental data reported in the literature.

show abstract

Section: Introductionmentioning

confidence: 99%

Modeling the dependence of strength on grain sizes in nanocrystalline materials

Bhole

Chen

2008

Science and Technology of Advanced Materials

View full text Add to dashboard Cite

show abstract

“…In particular, we have established (i) A model for the grain size dependence of the yield strength of nanostructures, (ii) A model for the critical grain size and strain rate necessary for dislocation-based plasticity in nanostructures, (iii) A gradient elasticity model for nanostructures with application to predicting oscillatory crack profiles, (iv) Two plasticity models for nanostructures accounting for nanopore growth and coalescence and (v) A model of shear band inclination and thickness analysis in relation to the observed asymmetry in tension/compression of bulk nanostructures. Some of these results can be found in Refs [110] for (i), [131,132] for (iii), [107] and [113] for (iv). Results on (ii) and (v) can also be found in Refs [115] and [116,117] and these will also be summarized below:…”

Section: Modeling the Mechanical Properties Of Nanostructuresmentioning

confidence: 89%

“…Details on all the above issues related to thin films and bulk nanostructures can be found in Refs [106][107][108][109][110][111][112][113][114][115][116][117][118][119].…”

Section: Background and State Of The Artmentioning

confidence: 99%

Experimental and Theoretical Studies of Spatio-Temporal Instabilities in Novel Materials

Aifantis¹,

Hackney²,

Milligan³

2000

View full text Add to dashboard Cite

“…One of the earliest modelling approaches to the analysis of strength of nanomaterials based on the rule-of-mixture was suggested by Carsley et al [21]. A material is considered as consisting of two phases: squared grains with bulk properties and the boundary phase, which represent a metallic (amorphous) glass material.…”

Section: Composite Models Of Nanocrystalline Metallic Materialsmentioning

confidence: 99%

“…Among the constitutive laws used in some models, one can list the grain size dependent plasticity (for grain interior/GI) and amorphous glass model (GB) [21], anisotropic elasto-plastic models with different orientations (GI) and Voce-hardening law with high work hardening rate. Depending on the distance from the closest grain boundary (GB) [33,35], isotropic, linear hardening behaviour (GI) and isotropic power-law type rate dependent constitutive response (GB) [27], dislocation glide model (GI) and diffusional (Coble creep and Nabarro-Herring creep) deformation [22][23][24][25], unified viscoplastic constitutive law [6], elastic-viscoplastic behaviour and dislocation glide (GI) and elastic perfect plastic behaviour incorporating the model of grain boundary dislocation emission and penetration (GB) [33][34][35][36][37][38][39][40], crystal viscoplasticity with Hall Petch grain size dependence (GI) and isotropic viscoplasticity and Mohr-Coulomb pressure dependence (GB) [47] .…”

Section: Dislocation Mechanisms Of Deformation and Polycrystal Plastimentioning

confidence: 99%

Micromechanical modelling of nanocrystalline and ultrafine grained metals: A short overview

Mishnaevsky

Левашов

2015

Computational Materials Science

View full text Add to dashboard Cite

Abstract:An overview of micromechanical models of strength and deformation behaviour of nanostructured and ultrafine grained metallic materials is presented. Composite models of nanomaterials, polycrystal plasticity based models, grain boundary sliding, the effect of nonequilibrium grain boundaries and nanoscale properties are discussed and compared. The examples of incorporation of peculiar nanocrystalline effects (like large content of amorphous or semi-amorphous grain boundary phase, partial dislocation GB emission/glide/GB absorption based deformation mechanism, diffusion deformation, etc.) into continuum mechanical approach are given. The possibilities of using micromechanical models to explore the ways of the improving the properties of nanocrystalline materials by modifying their structures (e.g., dispersion strengthening, creating non-equilibrium grain boundaries, varying the grain size distributions and gradients) are discussed.Keywords: Micromechanics; Finite element modelling; Nanomaterials; Nanocrystalline materials IntroductionDuring recent decades, growing interest of scientific community has been attracted to the nanostructured materials. The expectations on nanostructuring as a way to enhance material performances and to improve competing materials properties are very high, and some of them have been delivered, indeed.The extraordinary properties of nanocrystalline and ultrafine grained metallic materials (i.e., materials with the grain sizes of the order of several to several hundred nanometers) include superductility at room temperature, high hardness and high strength 2 to hardness value (which might be 2…7 times higher than in coarse grained materials), lower elastic modulus, negative Hall-Petch slope, enhanced strain rate sensitivity and difference between tensile and compression response [1][2][3][4][5]. The yield strength of nanocrystalline materials can be up to 5…10 times higher than of coarse-grained materials [6]. Other peculiar effect of nanocrystalline materials are the deviation fromHall-Petch relation at ultrafine and nanoscale grain sizes (below 100 nm), which goes into negative Hall Petch slope at about 10 nm, as well as asymmetry of tensile and compressive behaviour and enhanced diffusion properties [7].In order to predict the service properties of the materials and to explore the potential and reserves of their improvement, computational models linking the macroscale (service) In this paper, we present an overview of micromechanical models of nanocrystalline and ultrafine grained materials, their mechanical behaviour, deformation and strength.Composite models, crystal plasticity based models, grain boundary sliding, the effect of non-equilibrium grain boundaries, etc. are reviewed. The main constraints and challenges in the considered models are discussed. Composite models of nanocrystalline metallic materialsThe main structural feature of nanocrystalline and ultrafine grained materials, apart from the small grain sizes, is the high relative volume of grain boundary surface pha...

show abstract

A simple, mixtures-based model for the grain size dependence of strength in nanophase metals

Cited by 161 publications

References 37 publications

Modeling the dependence of strength on grain sizes in nanocrystalline materials

Modeling the dependence of strength on grain sizes in nanocrystalline materials

Experimental and Theoretical Studies of Spatio-Temporal Instabilities in Novel Materials

Micromechanical modelling of nanocrystalline and ultrafine grained metals: A short overview

Contact Info

Product

Resources

About