Texture Evidences of Interaction between Plastic Deformation and Phase Transformations in Zr-Based Alloys

Abstract. Features of the texture development in Zr-based alloys under compression at tempera-tures of the (α+β)-region of the Zr-Nb phase diagram indicate that the plastic deformation shifts temperatures of phase transformations due to accompanying thermal effects and the decrease of lattice stability, whereas formation of the fine-grained structure by phase transformation promotes activation of the non-crystallographic deformation mechanism of slip by interphase boundaries.

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Plastic Deformation of Zr-Based Alloys at Temperatures of Phase Transformations

Materials Science Forum ◽

10.4028/www.scientific.net/msf.550.637 ◽

2007 ◽

Vol 550 ◽

pp. 637-642

Author(s):

Margarita Isaenkova ◽

Yuriy Perlovich ◽

Vladimir Fesenko ◽

Thant Zaw Htike ◽

S. Kropachev ◽

...

Keyword(s):

Phase Diagram ◽

Plastic Deformation ◽

Phase Transformations ◽

Uniaxial Compression ◽

Deformation Behavior ◽

Β Phase ◽

Crystallographic Slip ◽

Interphase Boundaries ◽

Temperatures Of Phase Transformations ◽

Temperature Rate

Deformation behavior of Zr-Nb alloys under uniaxial compression, accompanied by phase transformations, is considered by the example of Zr-1%Nb and Zr-2.5%Nb alloys. Model samples were deformed at temperatures of β- and (α+β)-regions of the phase diagram Zr-Nb. Mechanisms, responsible for plastic deformation of alloys by different temperature-rate regimes, were determined on the basis of textures, arising in deformed samples. Among these mechanisms there are crystallographic slip in grains of β-Zr and α-Zr as well as mutual displacements of crystallites along interphase boundaries. The latter mechanism sharply intensifies under conditions of α↔β phase transformations and lies in the basis of superplasticity. An input of each mechanism into plastic deformation of material depends on the temperature-rate regime of compression and determines its anisotropy.

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Texture Development in Zr-Based Alloys by High-Temperature Forging as Indicator of Interaction between Plastic Deformation and α↔β Phase Transform Actions

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.160.123 ◽

2010 ◽

Vol 160 ◽

pp. 123-128

Author(s):

Margarita Isaenkova ◽

Yuriy Perlovich ◽

Vladimir Fesenko ◽

Sergey Kropachev ◽

Olga Krymskaya

Keyword(s):

Phase Diagram ◽

Plastic Deformation ◽

High Temperature ◽

Phase Transformations ◽

Deformation Behavior ◽

Β Phase ◽

Phase Transform ◽

Crystallographic Slip ◽

Interphase Boundaries ◽

Temperature Rate

Deformation behavior of Zr-based alloys by forging under conditions of α↔β phase transformations was considered as applied to model samples and real semi-products. Model samples were deformed by uniaxial compression at temperatures of β- and (α+β)-regions of the phase diagram Zr-Nb. Mechanisms, responsible for plastic deformation of alloys by different temperature-rate regimes, were determined on the basis of textures, arising in deformed samples. Among these mechanisms there are crystallographic slip in grains of β-Zr and α-Zr as well as mutual displace¬ments of crystallites along interphase boundaries. The latter mechanism sharply intensifies under conditions of α«β phase transformations and lies in the basis of superplasticity. An input of each mechanism into plastic deformation of material depends on the temperature-rate regime of compression and determines its anisotropy.

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Evidence of Bulk Nanostructuring in Zr-Based Alloys under Deformation at Temperatures of α↔β Phase Transformations

Materials Science Forum ◽

10.4028/www.scientific.net/msf.667-669.629 ◽

2010 ◽

Vol 667-669 ◽

pp. 629-634

Author(s):

Margarita Isaenkova ◽

Yuriy Perlovich ◽

Vladimir Fesenko ◽

Olga Krymskaya ◽

Alexander Zavodchikov

Keyword(s):

Plastic Deformation ◽

Phase Transformations ◽

Texture Features ◽

X Ray ◽

Β Phase ◽

Crystallographic Slip ◽

Interphase Boundaries ◽

Grain Fragmentation ◽

Temperature Rate ◽

Zr Alloys

The deformation behavior of commercial Zr alloys with 1% and 2,5%Nb under compression at temperatures of the (α+β)-region of Zr-Nb phase diagram is considered on the basis of experimental data obtained by X-ray texture study of deformed samples. Mechanisms, responsible for plastic deformation of alloys by different temperature-rate regimes were determined on the basis of resulting textures. Among these mechanisms there are crystallographic slip and mutual displacements of crystallites along interphase boundaries. The latter mechanism sharply intensifies by grain fragmentation down to nanostructuring under conditions of α«β phase transformations. Texture features of deformed samples testify about interaction of plastic deformation with phase transformations and indicate that due to this interaction compression by optimal regimes promotes the utmost refinement of structure elements.

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Phase Transformations of the Ti-40% Nb Alloy Under External Influence

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.683.174 ◽

2016 ◽

Vol 683 ◽

pp. 174-180 ◽

Cited By ~ 1

Author(s):

Yuri P. Sharkeev ◽

Zhanna G. Kovalevskaya ◽

Margarita A. Khimich ◽

Vladimir A. Bataev ◽

Qi Fang Zhu ◽

...

Keyword(s):

Plastic Deformation ◽

Phase Transformation ◽

Severe Plastic Deformation ◽

Phase Transformations ◽

Optical Metallography ◽

External Influence ◽

Β Phase ◽

Α Phase ◽

Pressing Operation ◽

Loading Axis

The phase transformations of the alloy Ti-40 mas % Nb after tempering and severe plastic deformation are studied. The phase transformations of the alloy according to the type and conditions of external influences are analyzed using methods of XRD, SEM and optical metallography. It is determined that inverse phase transformation of the metastable α''-phase to equilibrium β-phase is carried out after severe plastic deformation. Complete phase transformation α'' → β is typical for the mode, which consists of three pressing operation with the change of the loading axis in cramped conditions, followed by a multi-pass rolling in grooved rolls.

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Study of Phase Transformation in Alloys of the Al-Fe System

Defect and Diffusion Forum ◽

10.4028/www.scientific.net/ddf.326-328.573 ◽

2012 ◽

Vol 326-328 ◽

pp. 573-577 ◽

Cited By ~ 5

Author(s):

Magdalena Jabłońska ◽

Marta Mikuśkiewicz ◽

Anna Śmiglewicz ◽

E. Bernstock-Kopaczyńska

Keyword(s):

Thermal Analysis ◽

Solid Solution ◽

Phase Transformation ◽

Phase Transformations ◽

Order Type ◽

Point Of View ◽

Gravity Casting ◽

Mechanical And Physical Properties ◽

Temperatures Of Phase Transformations ◽

Alloys Of The Al

In this paper, phase transformation in alloys of the Al-Fe and Al-Fe-Cr systems was investigated. The alloys were prepared by melting and gravity casting. The studies of phase transformation were carried out on samples after casting and annealing, using the differential thermal analysis (DTA) and dilatometric method. The knowledge on the phase transformations in these alloys including the information about order-disorder transition is very important from the point of view of obtained mechanical and physical properties of alloys of the Al-Fe system. These results are an important contribution in development of knowledge on iron aluminides. In the article, temperatures of phase transformations connected with a change in order type and transition into disordered solid solution were defined. Conformity of the recorded DTA results and dilatometric analysis was achieved.

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Fine-grained structure and recrystallization at ambient temperature for pure magnesium subjected to large cold plastic deformation

Materials Science and Engineering A ◽

10.1016/j.msea.2017.10.020 ◽

2017 ◽

Vol 708 ◽

pp. 351-359 ◽

Cited By ~ 5

Author(s):

X.M. Chen ◽

L.T. Li ◽

W.Z. Chen ◽

W.C. Zhang ◽

L.X. Zhang ◽

...

Keyword(s):

Plastic Deformation ◽

Ambient Temperature ◽

Pure Magnesium ◽

Cold Plastic Deformation ◽

Fine Grained ◽

Fine Grained Structure

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Structural Characterization of FeAl28Cr5 Alloy Deformed in the Hot Torsion Process

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.246.43 ◽

2016 ◽

Vol 246 ◽

pp. 43-46 ◽

Cited By ~ 1

Author(s):

Iwona Bednarczyk ◽

Magdalena Jabłońska

Keyword(s):

Plastic Deformation ◽

Grain Size ◽

Structural Changes ◽

Al Alloys ◽

Dynamic Processes ◽

Fine Grained ◽

Average Grain Size ◽

Fine Grained Structure ◽

Hot Torsion

Current research in the field of iron aluminides are directed towards to understand the structural phenomena occurring during plastic deformation of these alloys. The obtained results of the study and collected informations will be used to determine the description of the structural changes taking place during hot deformation of Fe ̶Al alloys. The article presents the results of the study of the alloy FeAl28Cr5 deformed by hot torsion in temperature range of 800÷1100°C and a strain rate of 0.1 s-1. The analysis of the structure of the alloy FeAl28Cr5 allowed to reveal changes caused by dynamic processes of deformation. The results of torsion tests show the possibility to obtain a fine-grained structure with of parameters of the processes (T=1000°C, 1100°C) and strain of ε=40. After deformation at strain of (ε=40) the structure consists of fine grains with a misorientation angle higher than 15°, and the average grain size diameter D=28.5 micrometers. Deformation at a temperature of T=1000°C and 1100°C is accompanied by superplastic flow effect.

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Development of Ultra-Fine Grained Structure in an Al-5.4%Mg-0.5%Mn Alloy Processed by ECAP

Materials Science Forum ◽

10.4028/www.scientific.net/msf.667-669.487 ◽

2010 ◽

Vol 667-669 ◽

pp. 487-492

Author(s):

Alla Kipelova ◽

Ilya Nikulin ◽

Sergey Malopheyev ◽

Rustam Kaibyshev

Keyword(s):

Plastic Deformation ◽

Structure Formation ◽

Equal Channel Angular Pressing ◽

Microstructural Evolution ◽

Coarse Grained ◽

High Angle ◽

Fine Grained ◽

Angular Pressing ◽

Fine Grained Structure ◽

Zr Alloy

Microstructural changes during equal channel angular pressing (ECAP) at the temperatures of 250 and 300°C to the strains ~4, ~8 and ~12 were studied in a coarse-grained Al-5.4%Mg-0.5%Mn-0.1%Zr alloy. At a strain of ~4, the microstructural evolution is mainly characterized by the development of well-defined subgrains within interiors of initial grains and the formation of fine grains along original boundaries. Further straining leads to increase in the average misorientation angle, the fraction of high-angle grain boundaries and the fraction of new grains. However, only at 300°C, the plastic deformation to a strain of ~12 leads to the formation of almost uniform submicrocrystalline (SMC) grained structure with an average crystallites size of ~ 0.5 m. At 250°C, the microstructure remains non-uniform and consists of subgrains and new recrystallized grains. The mechanism of new SMC structure formation after ECAP is discussed.

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