Dynamic recrystallization kinetics

Roberts, W. T.; Boden, H.; Ahlblom, Bertil

doi:10.1179/msc.1979.13.3-4.195

Cited by 131 publications

(61 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As recrystallized grains nucleate in previous austenite grain boundaries, increasing the initial grain size, grain boundary area per unit volume decreases, producing a delay in the kinetics, as usually reported. 15,16) In Fig. 6 the peak strains determined for each condition have been indicated.…”

Section: Drx Fraction and Post-dynamic Softening Interactionmentioning

confidence: 99%

“…[7][8][9][10][11][12] The dynamic recrystallization (DRX) kinetics in C-Mn and microalloyed steels have been studied many times. [13][14][15][16][17][18] The onset of DRX during hot deformation occurs when a critical strain e c is reached. This critical strain is related to the peak strain e p , i.e.…”

Section: Introductionmentioning

confidence: 99%

“…The various grain sizes plotted for the same value of Z, correspond to different initial microstructures and although there is experimental scatter, it can be concluded that the steady state microstructure is independent of the initial one, as is commonly reported in the literature. 15,16,28) For a given composition a power relationship between the dynamically recrystallized grain size and the Z parameter is usually proposed. [28][29][30] The set of data corresponding to each steel can be fitted to a power relationship, with the same exponent value (Ϫ0.13) for all the materials, and the proportionality constant dependent on each steel: It should be noted that both Nb-Mo steels show a slightly smaller grain size than the Nb steel (see Fig.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Effect of Mo on Dynamic Recrystallization Behavior of Nb-Mo Microalloyed Steels

et al. 2007

View full text Add to dashboard Cite

The influence of the Mo addition on the dynamic recrystallization behavior of Nb microalloyed steels was studied. The initial austenite grain size, the amount of microalloying elements in solid solution and the deformation conditions (temperature and strain rate) affect dynamic recrystallization kinetics of both Nb and Nb-Mo steels. Continuous torsion tests were carried out to characterize the dynamic recrystallization behavior of the microalloyed austenite, after reheating the specimens at different temperatures between 1 100 and 1 460°C, this brought a wide range of initial grain sizes, from 22 to 805 mm. It was observed that decreasing the values of the Zener-Hollomon parameter and of the initial grain size promotes dynamic recrystallization. Mo in solid solution produces a large retardation effect in the dynamic recrystallization and brings higher values in the characteristic critical, e c , and peak, e p , strains, being this effect independent of the Mo content. A corrective factor has been applied to quantify the retardation produced by Mo in solid solution. This means that it was possible to propose a unique relationship to predict the peak strain for Nb, Nb-Ti and Nb-Mo steels.KEY WORDS: dynamic recrystallization; hot direct rolling; Nb and Nb-Mo microalloyed steels.ISIJ International, Vol. 47 (2007), No. 6, solute effect on the dynamic recrystallization kinetics leading to a significant retardation in the process. [1][2][3][4] However, this effect has not been yet quantified. This is an important issue, taking into account that any retardation of dynamic recrystallization could affect the design of the appropriate thin slab rolling sequences, above all for the initial stands, so that a correct refinement of the as-cast austenite can be achieved before niobium precipitation occurs. 19) This paper studied the DRX events for those steels containing Nb and Mo at the same time. A study was carried out to determine the effect of the initial austenite grain size, within a wide range of grain sizes, and the deformation conditions on DRX kinetics. Material and Experimental ProcedureFour Nb-Mo microalloyed steels were studied and the results compared to a Nb microalloyed steel. A 0.035 % Nb microalloyed base steel and two levels of Mo, 0.15 and 0.31, were considered. All the Nb-Mo steels were experimental casts. The chemical compositions of the steels studied are listed in Table 1. The results obtained with the Nb steel were described in detail in a previous work 18) but they will be used here for assessing the individual and combined effects. Isothermal torsion tests were performed after soaking the specimen at different temperatures in the range of 1 100-1 460°C for 15 min in an argon atmosphere to analyze the DRX behavior. Torsion samples were machined from 40 mm thickness plates in the case of Nb, Nb-Mo31b and Nb-Mo16 steels and from 40 mm diameter bars in the case of Nb-Mo31a and Nb-Mo15 steels, respectively. Coarse austenite microstructures (Ϸ600-800 mm) were produced by reheating at high temperatures, in ...

show abstract

Section: Drx Fraction and Post-dynamic Softening Interactionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Effect of Mo on Dynamic Recrystallization Behavior of Nb-Mo Microalloyed Steels

et al. 2007

View full text Add to dashboard Cite

show abstract

“…During DRX if the strain rateε is constant, the time in Eq. (17) is usually replaced by t = (ε − ε c )/ε and the kinetics can again be analyzed using the Avrami equation (Roberts et al, 1979), which is shown in Fig. 11.…”

Section: Kinetics Of Drxmentioning

confidence: 99%

An integrated full-field model of concurrent plastic deformation and microstructure evolution: Application to 3D simulation of dynamic recrystallization in polycrystalline copper

Zhao

Low

Wang

et al. 2016

International Journal of Plasticity

107

View full text Add to dashboard Cite

Many time-dependent deformation processes at elevated temperatures produce significant concurrent microstructure changes that can alter the mechanical properties in a profound manner. Such microstructure evolution is usually absent in mesoscale deformation models and simulations. Here we present an integrated full-field modeling scheme that couples the mechanical response with the underlying microstructure evolution. As a first demonstration, we integrate a fast Fourier transform-based elasto-viscoplastic (FFT-EVP) model with a phase-field (PF) recrystallization model, and carry out three-dimensional simulations of dynamic recrystallization (DRX) in polycrystalline copper. A physics-based coupling between FFT-EVP and PF is achieved by (1) adopting a dislocation-based constitutive model in FFT-EVP, which allows the predicted dislocation density distribution to be converted to a stored energy distribution and passed to PF, and (2) implementing a stochastic nucleation model for DRX. Calibrated with the experimental DRX stress-strain curves, the integrated model is able to deliver full-field mechanical and microstructural information, from which quantitative description and analysis of DRX can be achieved. It is suggested that the initiation of DRX occurs significantly earlier than previous predictions, due to heterogeneous deformation. DRX grains are revealed to form at both grain boundaries and junctions (e.g., quadruple junctions) and tend to grow in a wedge-like fashion to maintain a triple line (not necessarily in equilibrium) with old grains. The resulting stress redistribution due to strain compatibility is found to have a profound influence on the subsequent dislocation evolution and softening.

show abstract

“…Roberts et al [18] suggests that DRX is initially manifested by a necklace of new grains at original grain boundaries. After these nucleation sites are fully occupied, DRX progresses sequentially via continuous nucleation at and along the more recently created interfaces between recrystallised grains and the deformed matrix.…”

Section: Introductionmentioning

confidence: 99%

Microstructure and micro-texture evolution during the dynamic recrystallisation of a Ni-30Fe-Nb-C model alloy

Mannan

Saleh

Gazder

et al. 2016

Journal of Alloys and Compounds

View full text Add to dashboard Cite

Pereloma, E. V. (2016). Microstructure and micro-texture evolution during the dynamic recrystallisation of a Ni-30Fe-Nb-C model alloy. Journal of Alloys and Compounds, Microstructure and micro-texture evolution during the dynamic recrystallisation of a Ni-30Fe-Nb-C model alloy AbstractThe evolution of microstructure and micro-texture during discontinuous dynamic recrystallisation of an austenitic Ni-30Fe-Nb-C model alloy subjected to interrupted plane strain compression at strains (ε) of 0.23, 0.35, 0.68, 0.85 and 1.2 was investigated using electron backscattering diffraction and transmission electron microscopy. Throughout the strain range, the majority of dynamic recrystallisation events comprised nucleation in necklace-like arrangements located at and along grain boundaries via bulging. At ε ≥ 0.68, discrete nucleation events were also observed within grain interiors. Grain growth during dynamic recrystallisation is characteristic of strain induced boundary migration. The initial texture comprised Cube-RD ({013}〈100〉), Cube-ND ({001}〈310〉) and Cube ({001}〈100〉) orientations. Up to ε ≤ 0.35, the unrecrystallised grain fractions comprised the Brass ({110}〈112〉) or Copper ({112}〈111〉) orientations and an intensity spread near Rotated Goss ({011}〈011〉). Between 0.68 ≤ ε ≤ 1.2, the texture of the unrecrystallised grain fractions was similar to that of the recrystallised grains throughout the strain range; both of which are dominated by the Cube orientation. The dominance of the Cube orientation in the secondary deformed and recrystallised grains can be ascribed to its low stored energy and orientation stability.

show abstract

Dynamic recrystallization kinetics

Cited by 131 publications

References 7 publications

Effect of Mo on Dynamic Recrystallization Behavior of Nb-Mo Microalloyed Steels

Effect of Mo on Dynamic Recrystallization Behavior of Nb-Mo Microalloyed Steels

An integrated full-field model of concurrent plastic deformation and microstructure evolution: Application to 3D simulation of dynamic recrystallization in polycrystalline copper

Microstructure and micro-texture evolution during the dynamic recrystallisation of a Ni-30Fe-Nb-C model alloy

Contact Info

Product

Resources

About