Dependence of the functional characteristics of thermomechanically processed titanium nickelide on the size of the structural elements of austenite

Polyakova-Vachiyan, K. A.; Рыклина, Е. П.; Прокошкин, С. Д.; Dubinskii, S. M.

doi:10.1134/s0031918x16080123

Cited by 15 publications

(5 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At the same time, their fractions are comparable (figure 4 a). A similar structure was obtained in the Ti -50.7 at.% Ni alloy after cold rolling and the same annealing [5,6]. The average size of structural elements is d = 30 ± 3 nm, the minimum is 10 nm, and the maximum does not exceed 90 nm.…”

Section: Resultssupporting

confidence: 72%

“…It should be noted that in the study of structure formation in the alloy Ti'50.2 at.%Ni, its traditional exposure at a temperature interval of 400-450 С 1 h, however, the work showed that the alloy Ti-50.7 at.%Ni in a nanostructural state after aging at an optimal temperature of 430С, 10 h Ti 3 Ni 4 phase particles are not visualized but are defined by X-ray and electron [4][5][6][7]. There is also no data on the effect of burn-off on the calorimetric effects of martensite transformations in the original crystallized structure.…”

Section: Introductionmentioning

confidence: 93%

See 1 more Smart Citation

Electronic tricroscopic examination of the structure of the Ti-50.2 at. % Ni alloy

et al. 2021

View full text Add to dashboard Cite

The method of electron-microscopic analysis investigated the structure of the alloy Ti-50.2 at % Ni at different stages of dissolution; low-temperature thermomechanical treatment (LTTT), post-deformation edgy (PDE), and recrystallization. The microstructure of B2-austenite, which is formed in the process of incoordination, was also investigated, including in the conditions of isothermic burning of the original recrystallized structure.

show abstract

Section: Resultssupporting

confidence: 72%

Section: Introductionmentioning

confidence: 93%

Electronic tricroscopic examination of the structure of the Ti-50.2 at. % Ni alloy

et al. 2021

View full text Add to dashboard Cite

show abstract

“…Numerous individual point reflections are also present. These electron diffraction patterns are characteristic of the regions with a mixed polygonized (nanosubgrained) and nanograined structure [9][10][11]. The statistical analysis of the structure elements size was carried out using bright field images in which the boundaries of grains and subgrains are clearly visualized in contrast to the dark field images, where not all subgrain boundaries can be distinguished.…”

Section: Resultsmentioning

confidence: 99%

Manufacturing of Long-Length Rods of Ultrafine-Grained Ti-Ni Shape Memory Alloys

Прокошкин¹,

Khmelevskaya²,

Андреев³

et al. 2018

MSF

View full text Add to dashboard Cite

Ti-Ni shape memory alloys were subjected to a rotary forging (RF) from the diameter of 20 or 12 mm to 5 mm at relatively low temperatures of 450 and 350 °C. The structure was studied using X-ray diffraction analysis and transmission electron microscopy. Mechanical properties were determined by uniaxial tensile and Vickers hardness tests, and the maximum completely recoverable strain by a thermomechanical method. The obtained results showed that RF at low temperatures allows manufacturing 3 m-long Ti-Ni rods. A mixed submicrocrystalline and nanosubgrained structure with an average size of structural elements of 118 ± 7 nm after forging from 20 mm, and 126 ± 7 nm after forging from 12 mm at 350 °С provides the highest mechanical (σв= 1113 MPa after forging from 20 mm, and 1065 MPa after forging from 12 mm) and functional (maximum completely recoverable strain of 8.0 %, after post-deformation annealing at 400 °С, 1 h) properties as compared to the initial state before RF (700 MPa, and 4.4 %, respectively).

show abstract

“…Functional and mechanical properties of Ti-Ni SMA are structure-sensitive and can be greatly improved by the formation of well-developed dislocation substructure or ultrafine-grained structure using various modes of thermomechanical treatment (TMT), including severe plastic deformation (SPD) [9][10][11][12][13][14][15]. It was shown in [16,17] that the formation of an ultrafine-grained structure allows to increase the maximum completely recoverable strain up to 9%.…”

Section: Introductionmentioning

confidence: 99%

“…However, in this alloy, deformation in the temperature range of 250-500 °C is accompanied by the dynamic strain aging with precipitation of Ni 4 Ti 3 particles, which have a great impact on phase transformations, properties and structure formation. This feature of aging Ti-Ni alloys leads to significant differences as compared to an unaged equiatomic Ti-Ni SMA [1,11,14]. These conditions make a similar study of the equiatomic alloy topical.…”

Section: Introductionmentioning

confidence: 99%

Deformation Behavior, Structure and Properties of an Equiatomic Ti–Ni Shape Memory Alloy Compressed in a Wide Temperature Range

Komarov

Khmelevskaya

Karelin

et al. 2021

Trans Indian Inst Met

View full text Add to dashboard Cite

In the present work, flow curves of an equiatomic Ti-Ni shape memory alloy after deformation by compression in the temperature range from 100 to 900 °C at a strain rate of 1 s -1 and up to a true strain (e) of 0.9 were obtained. The phase composition, mechanical and functional properties after compression to e = 0.5 were studied. The boundaries of the temperature ranges of the development of dynamic softening processes were determined, as follows: dynamic recovery in 100-300 °C range; dynamic polygonization in 300-500 °C range and dynamic recrystallization above 500 °C. An optimum deformation temperature range in terms of accumulation of high strains and achieving improved functional properties is 300-500 °C. It has also been found that post-deformation annealing at temperatures above the deformation temperature leads to the decrease in the B2-austenite lattice defectness and to a significant increase in shape recovery characteristics.

show abstract

Dependence of the functional characteristics of thermomechanically processed titanium nickelide on the size of the structural elements of austenite

Cited by 15 publications

References 14 publications

Electronic tricroscopic examination of the structure of the Ti-50.2 at. % Ni alloy

Electronic tricroscopic examination of the structure of the Ti-50.2 at. % Ni alloy

Manufacturing of Long-Length Rods of Ultrafine-Grained Ti-Ni Shape Memory Alloys

Deformation Behavior, Structure and Properties of an Equiatomic Ti–Ni Shape Memory Alloy Compressed in a Wide Temperature Range

Contact Info

Product

Resources

About