Large and Severe Plastic Deformation of Metals: Similarities and Differences in Flow Mechanics and Structure Formation

Utyashev, F. Z.; Beygelzimer, Yan; Valiev, Ruslan Z.

doi:10.1002/adem.202100110

Cited by 8 publications

(3 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…12-23 changing (shear) component of deformation taken into account in the calculations. In the physics of strength and plasticity [8,9], along with the shear component, the crystal structure of metallic materials is also influenced by the rotational component, which is especially important in the technological processes of manufacturing large-sized UFG semi-finished products. For this reason, such processes can be classified as methods that provide extremely large deformations.…”

Section: Introductionmentioning

confidence: 99%

Rational Methods of Plastic Deformation Providing Formation of Ultrafine-Grained Structure in Large-Sized Products

Utyashev,

Botkin,

Volkova

et al. 2024

Rev. Adv. Mater. Technol.

Self Cite

View full text Add to dashboard Cite

Based on the peculiarities of plastic deformation mechanics and physical mesomechanics, the processes are considered and technological schemes for their realization are proposed to ensure the formation of ultrafine-grained structure in axisymmetric products of large sizes. Deformation of coarse-grained materials in temperature-velocity conditions of superplastic deformation and methods of severe plastic deformation are taken as methods of preparation of such a structure. All of these deformations include large strain, and they are carried out at low hydraulic press speeds, but at different temperatures: in the mode of superplasticity at hot temperatures, and in the mode of severe plastic deformation at warm or cold temperature deformation. The first mode allows grains to be refined to microcrystalline sizes of 1–10 microns, and such a material acquires the ability to deform in a state of superplasticity, i.e., in tension with low resistance to deformation and high elongation. The second mode (severe plastic deformation) refines grains to submicro- (1÷0.1 µm) and nanosizes (less than 0.1 µm), thus giving metal materials record structural strength, as well as the possibility to use processing in extended temperature-velocity conditions of superplastic deformation in comparison with microcrystalline structure.

show abstract

Section: Introductionmentioning

confidence: 99%

Rational Methods of Plastic Deformation Providing Formation of Ultrafine-Grained Structure in Large-Sized Products

Utyashev,

Botkin,

Volkova

et al. 2024

Rev. Adv. Mater. Technol.

Self Cite

View full text Add to dashboard Cite

show abstract

“…It is known that the refinement of the grain-subgrain structure of metals and alloys significantly affects their functional and mechanical properties [1,2]. One of the ways to significantly reduce the size of grains-subgrains is to apply a large plastic deformation to the samples by the methods of severe plastic deformation (SPD) [3,4]. The refinement of grains-subgrains under SPD leads to the hardening of metals and alloys [1,2,5].…”

Section: Introductionmentioning

confidence: 99%

Effect of Isochronous Annealings on the Microstructure and Mechanical Properties of the Ti49.8Ni50.2 (at.%) Alloy after abc Pressing at 573 K

Lotkov,

Grishkov,

Laptev

et al. 2023

Metals

View full text Add to dashboard Cite

The regularities and features of the evolution of the grain–subgrain structure, phase composition and mechanical properties in Ti49.8Ni50.2 (at.%), depending on the temperature of isochronous annealings at 573–973 K are herein studied. The state of the Ti49.8Ni50.2 (at.%) alloy samples after abc pressing at T = 573 K with the given true strain e = 9.55 was taken as the initial state. It is shown that the grain–subgrain structure of the samples after annealing for 1 h in the temperature range of 573–673 K changes slightly. In samples annealed at 673 K, regions with the microband structure similar to the microstructure of a fast-frozen turbulent liquid flow were found. It has been established that during annealing at 773 K the beginning of an active recrystallization process is realized; the size of grains does not exceed the submicrocrystalline scale (~200 nm). At 873 K, the recrystallization process occurs in the entire volume of the samples; the grains with an average size of 2 ± 0.5 µm are almost equiaxed. The microstructure of the samples after annealing at 973 K (with average grain sizes of 5 ± 0.5 µm) is qualitatively similar to the microstructure of the samples after annealing at 873 K. It was found that the phase composition of the samples as a result of isochronous annealing at 573–973 K changes from R and B19’ immediately after abc pressing to a three-phase state: B2, R and B19’ phases. It is shown that the highest values of yield stress σy, ultimate tensile strength σUTS (1043 MPa and 1232 MPa, correspondingly) and low ductility (the deformation to fracture εf = 48%) are observed in the initial samples. Increasing the temperature of post-deformation annealing and, correspondingly, the development of recrystallization, led to a decrease in σy, σUTS and an increase in εf to the values of these characteristics in the coarse-grained samples (σy = 400 MPa, σUTS = 920 MPa and εf = 90%).

show abstract

“…Интенсивная пластическая деформация (ИПД), включая интенсивную пластическую деформацию кручением (ИПДК), является эффективным способом трансформации структуры металлических материалов, формирования в них наноструктурного состояния, значительного повышения прочности [1][2][3]. Метод ИПДК позволяет получать образцы для научных исследований в виде диска диаметром 10-20 мм и тол-щиной до 1 мм.…”

Section: Introductionunclassified

The investigation of the slippage effect, transformation of the structure and properties of the Zr–1%Nb alloy during high-pressure torsion deformation

Гундеров¹,

Stotsky²,

Aubakirova³

et al. 2022

FMT

View full text Add to dashboard Cite

High-pressure torsion deformation (HPT) is an effective method for transforming the structure of metallic materials, forming a nanostructural state in them, and significantly improving their strength. However, deformation achieved during HPT can be much less than expected due to the slippage. The study of the slippage effect during HPT of various materials is a topical issue. Previously, the authors proposed a simple and illustrative method for assessing slippage and the actual degree of torsion deformation achieved during HPT. Zr–1%Nb alloys, on which many studies of the HPT effect previously have been carried out, are good material for studying the slippage effect during HPT. Therefore, it is possible to compare obtained data with the results of other authors. The paper investigates the HPT impact on the structure and properties of the Zr–1%Nb alloy and demonstrates the slippage effect. The initial disk, prepared for HPT, was cut into two half-disks that were jointly placed on the strikers and exposed to joint HPT for n=¼ revolutions of anvils. The authors evaluated the slippage effect from the view of halves. The study showed that even at the initial HPT stages at n=¼ revolutions, there is a significant slippage of strikers and a sample, and the torsion deformation does not accumulate as expected. The authors analyzed the influence of various HPT modes on the microhardness, structure, and phase composition of the Zr–1%Nb alloy. The study shows that, despite the slippage effect, the Zr–1%Nb alloy is strongly hardened during HPT for one revolution (n=1) and HPT with n=10; the microhardness and tensile strength increase significantly, and up to 90 % of high-pressure ω-phases is formed in the sample. The authors conclude that during HPT, the deformation is implemented not by simple torsion but by the more complex modes.

show abstract

Large and Severe Plastic Deformation of Metals: Similarities and Differences in Flow Mechanics and Structure Formation

Cited by 8 publications

References 31 publications

Rational Methods of Plastic Deformation Providing Formation of Ultrafine-Grained Structure in Large-Sized Products

Rational Methods of Plastic Deformation Providing Formation of Ultrafine-Grained Structure in Large-Sized Products

Effect of Isochronous Annealings on the Microstructure and Mechanical Properties of the Ti49.8Ni50.2 (at.%) Alloy after abc Pressing at 573 K

The investigation of the slippage effect, transformation of the structure and properties of the Zr–1%Nb alloy during high-pressure torsion deformation

Contact Info

Product

Resources

About