Ultrafine grain formation in face centered cubic metals during severe plastic deformation

Sakai, Taku; Miura, Hiromi; Yang, Xuyue

doi:10.1016/j.msea.2007.11.098

Cited by 84 publications

(41 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The described changes are in a good agreement with the results reported in [22], where the authors using multi-directional compression (alternately in the x, y, and z directions) of technically pure copper, obtained an overall deformation e = 18 at the temperature range -78 to 200°C. Strengthening of material was increasing rapidly but its rate of strengthening in subsequent cycles decreased, reaching the state of plastic flow corresponding to dynamic recrystallization.…”

Section: Microstructural Evolution Upon Forgingsupporting

confidence: 90%

“…Based on the above observations and the results of other research [22,39,[41][42][43], we can try to generalize the phenomena of plastic deformation occurring during forging of an Fe 3 Al-based intermetallic alloy investigated in this work. In the initial stage of deformation, the enormous rise of the dislocation density occurs in the material.…”

Section: Discussionmentioning

confidence: 82%

“…New grains appear in the material which can achieve nanometric size and a large misorientation angle ([15°) if the width of the microbands is also sufficiently small (\500 nm). This mechanism is called the ''geometric mechanism of new grains formation'' [20][21][22][23][24]. The formation of ultrafinegrained structure is caused by a change in the direction of deformation (e.g., by rotation of sample) resulting in additional intersecting microbands.…”

Section: Introductionmentioning

confidence: 99%

“…The formation of ultrafinegrained structure is caused by a change in the direction of deformation (e.g., by rotation of sample) resulting in additional intersecting microbands. Finally, the original strongly deformed structure disappears during the structure rebuilding leading to the formation of grains and subgrains of different sizes dependent on conditions of deformation process [20][21][22][23]. For this reason, the structure of bulk materials deformed by the SPD methods may be sometimes quite diverse and may consist of volumes having both ultrafine and nanometric grains.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Multi-axial forging of Fe3Al-base intermetallic alloy and its mechanical properties

2016

View full text Add to dashboard Cite

Tri-axial plane-strain forging was applied to the Fe-28Al-5Cr-0.8Zr-0.04B intermetallic alloy, in order to study its grain refinement and possible improvement in mechanical properties. The forging temperature range was from 20 to 600°C. The maximum number of forging passes was 67. The deformed microstructure was investigated using electron backscatter diffraction in a scanning electron microscope. At forging temperatures \500°C, the alloy was very prone to brittle cracking. At the temperature range of 500-600°C, the overall plasticity of material increased and the cracking tendency was reduced but not completely eliminated. Extensive processes of dynamic recovery/recrystallization were observed during forging at 600°C after 10-40 passes. Recrystallized areas with an average grain size of a few micrometers were observed. However, even after severe deformation at 600°C, resulting from 40 forging passes (e * 11.3), dynamic recrystallization was incomplete and the fraction of low-angle boundaries was still high. The Vickers microhardness substantially increased from 280 HV0.1 to 450 HV0.1 at the center of the sample after both deformations at room temperature as well as after 20-40 cycles at 500-600°C. However, a further increase of strain for a sample deformed at 600°C after 67 passes (e * 28) led to quite a significant hardness decrease at the center of the sample. This phenomenon could be associated with the initiation of dynamic recrystallization. None of the samples forged at the 500-600°C range exhibited any ductility improvement during subsequent tensile testing at room temperature, most likely, owing to the absence of a uniform ultrafine-grained structure developed during forging.

show abstract

Section: Microstructural Evolution Upon Forgingsupporting

confidence: 90%

Section: Discussionmentioning

confidence: 82%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Multi-axial forging of Fe3Al-base intermetallic alloy and its mechanical properties

2016

View full text Add to dashboard Cite

show abstract

“…Alternatively, during plastic deformation of the material, dynamic recrystallization (DRX) can take place [5,6]. Experimental investigations have shown that dynamic recrystallization can in fact be subdivided into two main, physically different, processes [7][8][9]. In materials of low stacking-fault energy, such as copper, dynamic recovery processes such as cross slip and climb are limited and the microstructural evolution is dominated by discontinuous dynamic recrystallization (DDRX) during which new grains are nucleated at high-energy sites in the microstructure.…”

Section: Mechanics Of Recrystallizationmentioning

confidence: 99%

Approaches to Modeling of Recrystallization

Hallberg

2011

Metals

153

View full text Add to dashboard Cite

Control of the material microstructure in terms of the grain size is a key component in tailoring material properties of metals and alloys and in creating functionally graded materials. To exert this control, reliable and efficient modeling and simulation of the recrystallization process whereby the grain size evolves is vital. The present contribution is a review paper, summarizing the current status of various approaches to modeling grain refinement due to recrystallization. The underlying mechanisms of recrystallization are briefly recollected and different simulation methods are discussed. Analytical and empirical models, continuum mechanical models and discrete methods as well as phase field, vertex and level set models of recrystallization will be considered. Such numerical methods have been reviewed previously, but with the present focus on recrystallization modeling and with a rapidly increasing amount of related publications, an updated review is called for. Advantages and disadvantages of the different methods are discussed in terms of applicability, underlying assumptions, physical relevance, implementation issues and computational efficiency.

show abstract

Severe Plastic Deformation by Equal Channel Angular Pressing and Rolling: The Influence of the Deformation Path on Strain Distribution

et al. 2017

View full text Add to dashboard Cite

The present work compares two deformation techniques, rolling and Equal Channel Angular pressing (ECAP), and the response offered by three different materials that differ in Stacking Fault Energy (SFE): AA1010 Al, commercially pure Cu, and an austenitic stainless steel. The objective of this investigation is to study the effect of each deformation mode on tensile behavior, deformation mechanism, texture, and microstructure and to establish the influence of the stacking fault energy on said effects. The results show that the different strain paths of ECAP and rolling do not affect the strength, but rolling leads to an accentuated texture and thus to elastic and plastic anisotropy. This finding has practical relevance for micro manufacturing techniques. Furthermore, it is observed that lower SFE results in smaller domain size and higher dislocation density, which are microstructural details related to strength and to the work hardening capacity. Finally, both techniques are able to produce a high amount of high angle grain boundaries, a feature that characterizes refined microstructures. These processes operate at different strain rates; thus, in low SFE materials, a more effective grain fragmentation by deformation-induced twins is observed after the ECAP process.

show abstract

Ultrafine grain formation in face centered cubic metals during severe plastic deformation

Cited by 84 publications

References 18 publications

Multi-axial forging of Fe3Al-base intermetallic alloy and its mechanical properties

Multi-axial forging of Fe3Al-base intermetallic alloy and its mechanical properties

Approaches to Modeling of Recrystallization

Severe Plastic Deformation by Equal Channel Angular Pressing and Rolling: The Influence of the Deformation Path on Strain Distribution

Contact Info

Product

Resources

About