Size-Dependent Grain-Growth Kinetics Observed in Nanocrystalline Fe

Krill, Carl E.; Helfen, Lukas; Michels, D.; Natter, Harald; Fitch, Andrew N.; Masson, Olivier; Birringer, R.

doi:10.1103/physrevlett.86.842

Cited by 192 publications

(82 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Recent experimental results on the grain growth kinetics in ultra-fine grained Fe in a range of temperatures [7] can be seen as a confirmation of the predictions of the present model.…”

Section: Analysis Of Stability Against Grain Growthsupporting

confidence: 73%

“…In all cases the loss of energy associated with increase of GB area is compensated for by the energy profit in the bulk due to decomposition of supersaturated Figure 3. Time dependence of the grain size for Al of various levels of purity [7], compared with the prediction for the present mechanism (the lowest curve). Fig.…”

Section: Grain Refining Due To Vacancy Supersaturationmentioning

confidence: 99%

See 1 more Smart Citation

On the kinetics of grain growth inhibited by vacancy generation

et al. 2000

View full text Add to dashboard Cite

“…Recent experimental results on the grain growth kinetics in ultra-fine grained Fe in a range of temperatures [7] can be seen as a confirmation of the predictions of the present model.…”

Section: Analysis Of Stability Against Grain Growthsupporting

confidence: 73%

Section: Grain Refining Due To Vacancy Supersaturationmentioning

confidence: 99%

On the kinetics of grain growth inhibited by vacancy generation

et al. 2000

View full text Add to dashboard Cite

“…The applications of nanocrystalline materials are limited by the thermal stability, and the kinetics of thermal grain growth are critical for the structural stability of these materials. Both experimental and theoretical studies [9][10][11][12] have pointed out that grain growth kinetics in nanocrystalline materials may be different from that in coarse-grained materials. The nanoscale effects in the kinetics can arise from a variety of factors, such as the role of triple junctions or grain rotation.…”

mentioning

confidence: 99%

Linear Grain Growth Kinetics and Rotation in Nanocrystalline Ni

2007

View full text Add to dashboard Cite

We report three-dimensional atomistic molecular dynamics studies of grain growth kinetics in nanocrystalline Ni. The results show the grain size increasing linearly with time, contrary to the square root of the time kinetics observed in coarse-grained structures. The average grain boundary energy per unit area decreases simultaneously with the decrease in total grain boundary area associated with grain growth. The average mobility of the boundaries increases as the grain size increases. The results can be explained by a model that considers a size effect in the boundary mobility.

show abstract

“…Both experimental and theoretical studies [25][26][27][28] have pointed out that grain growth kinetics in nanocrystalline materials may be different from that in coarse-grained materials. The nanoscale effects in the kinetics can arise from a variety of factors, such as the role of triple junctions or grain rotation.…”

mentioning

confidence: 99%

Annealing twins in nanocrystalline fcc metals: A molecular dynamics simulation

2007

View full text Add to dashboard Cite

We report fully three-dimensional atomistic molecular dynamics studies of grain growth kinetics in nanocrystalline Cu of 5 nm average grain size. We observe the formation of annealing twins as part of the grain growth process. The grain size and energy evolution was monitored as a function of time for various temperatures, yielding an activation energy for the process. The atomistic mechanism of annealing twin formation from the moving boundaries is described. DOI: 10.1103/PhysRevB.75.184111 PACS number͑s͒: 61.72.Mm, 61.82.Rx Annealing twins in face-centered-cubic metals have been observed as early as 1897, 1-3 and are a prominent feature observed in routine metallography of these materials. The formation of these twins is usually associated with the process of grain growth that occurs during annealing at relatively high temperatures. Twin boundaries are usually flat and extend across an entire grain. The resulting density of twins after an annealing treatment is controlled by grainboundary energy, prior deformation, and resulting grain size. [4][5][6][7][8][9][10][11] The formation of annealing twins is a very common experimental observation; the fraction of annealing twins typically increases with annealing time and therefore with the amount of grain growth. Up to two to three twins per grain are typically observed, and it has been suggested that the nucleation and growth of twinning are mechanistically linked to anomalous grain growth. [12][13][14] In addition, it has been shown that imposed shear stresses during annealing of deformed fcc metals with low stacking fault energies tend to result in recrystallized microstructures containing higher fractions of twin boundaries than those annealed without an imposed shear stress. 13 This appears to be true also for materials deformed by severe plastic deformation where high residual shear stresses are present.The mechanisms by which annealing twins are formed are not completely understood. Current theories propose that accidents at growing grains and particularly faults on ͕111͖-type planes are responsible for the formation of annealing twins. [15][16][17][18] The models of twin formation generally require grain-boundary migration. In the model of Mahajan et al., 15 the nucleation of Shockley partial dislocations at growth accidents on ͕111͖ steps is associated with grain-boundary migration.In nanocrystalline materials, there is strong evidence that deformation occurs through emission of Shockley partial dislocations from grain boundaries which are absorbed in the opposing grain boundaries. These mechanisms based on partial dislocations lead to twinning when partial dislocations are emitted in adjacent ͕111͖-type planes. The deformation response of these materials has been studied using molecular dynamics simulation techniques, [19][20][21] and similar theoretical work can help in the detailed understanding of the process of twin formation during annealing treatments.In the present work, we report on relatively long molecular dynamics simulations of grain growt...

show abstract

Size-Dependent Grain-Growth Kinetics Observed in Nanocrystalline Fe

Cited by 192 publications

References 13 publications

On the kinetics of grain growth inhibited by vacancy generation

On the kinetics of grain growth inhibited by vacancy generation

Linear Grain Growth Kinetics and Rotation in Nanocrystalline Ni

Annealing twins in nanocrystalline fcc metals: A molecular dynamics simulation

Contact Info

Product

Resources

About