Influence of Temperature and Plastic Strain on Deformation Mechanisms and Kink Band Formation in Homogenized HfNbTaTiZr

Due to its outstanding ductility over a large temperature range, equiatomic HfNbTaTiZr is well-suited for investigating the influence of temperature and plastic strain on deformation mechanisms in concentrated, body centered cubic solid solutions. For this purpose, compression tests in a temperature range from 77 up to 1073 K were performed and terminated at varying plastic strains for comparison of plastic deformation behavior. The microstructure and chemical homogeneity of a homogenized HfNbTaTiZr ingot were evaluated on different length scales. The compression tests reveal that test temperature significantly influences yield strength as well as work hardening behavior. Electron backscatter diffraction aids in shedding light on the acting deformation mechanisms at various temperatures and strains. It is revealed that kink band formation contributes to plastic deformation only in a certain temperature range. Additionally, the kink band misorientation angle distribution significantly differs at varying plastic strains.

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Studying Deformation Behaviors in Austenitic Stainless Steels within a Temperature Range of 143 K < T < 420 K

PNRPU Mechanics Bulletin ◽

10.15593/perm.mech/2021.1.03 ◽

2021 ◽

pp. 22-30

Author(s):

S. A Barannikova ◽

A. M Nikonova ◽

S. V Kolosov

Keyword(s):

Plastic Deformation ◽

Plastic Strain ◽

Strain Localization ◽

Work Hardening ◽

Deformation Localization ◽

Linear Hardening ◽

Jerky Flow ◽

Temperature Range ◽

Α Phase ◽

Flow Stage

This work deals with studying staging and macroscopic strain localization in austenitic stainless steel 12Kh18N9T within a temperature range of 143 K < T < 420 K. The visualization and evolution of macroscopic localized plastic deformation bands at different stages of work hardening were carried out by the method of the double-exposure speckle photography (DESP), which allows registering displacement fields with a high accuracy by tracing changes on the surface of the material under study and then comparing the specklograms recorded during uniaxial tension. The shape of the tensile curves σ(ε) undergoes a significant change with a decreasing temperature due to the γ-α'-phase transformation induced by plastic deformation. The processing of the deformation curves of the steel samples made it possible to distinguish the following stages of strain hardening, i.e. the stage of linear hardening and jerky flow stage. A comparative analysis of the design diagrams (with the introduction of additional parameters of the Ludwigson equation) and experimental diagrams of tension of steel 12Kh18N9T for different temperatures is carried out. The analysis of local strains distributions showed that at the stage of linear work hardening, a mobile system of plastic strain localization centers is observed. The temperature dependence of the parameters of plastic deformation localization at the stages of linear work hardening has been established. Unlike the linear hardening, the jerky flow possesses the propagation of single plastic strain fronts that occur one after another through the sample due to the γ-α' phase transition and the Portevin-Le Chatelier effect. It was found that at the jerky flow stage, which is the final stage before the destruction of the sample, the centers of deformation localization do not merge, leading to the neck formation.

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Plastic deformation mechanisms of ultrafine-grained copper in the temperature range of 4.2–300 K

Low Temperature Physics ◽

10.1063/1.4964325 ◽

2016 ◽

Vol 42 (9) ◽

pp. 825-835 ◽

Cited By ~ 7

Author(s):

N. V. Isaev ◽

T. V. Grigorova ◽

O. V. Mendiuk ◽

O. A. Davydenko ◽

S. S. Polishchuk ◽

...

Keyword(s):

Plastic Deformation ◽

Deformation Mechanisms ◽

Temperature Range ◽

Ultrafine Grained

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Plasticity of decagonal Al73Ni10Co17 quasicrystals

MRS Proceedings ◽

10.1557/proc-805-ll5.5 ◽

2003 ◽

Vol 805 ◽

Author(s):

Peter Schall ◽

Michael Feuerbacher ◽

Knut Urban

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Plastic Deformation ◽

Deformation Mechanisms ◽

Compression Tests ◽

Compression Axis ◽

Decagonal Quasicrystal ◽

Transmission Electron ◽

Axis Parallel ◽

Means Of Transmission

ABSTRACTWe present a study of the deformation mechanism of decagonal Al73Ni10Co17 quasicrystals by means of transmission electron microscopy. We performed compression tests on single-quasicrystalline samples in three different orientations: with the compression axis parallel to, inclined by 45 ° and perpendicular to the tenfold axis of the decagonal quasicrystal. The deformed samples reveal characteristic orientation-dependent dislocation structures leading us to the conclusion that fundamentally different deformation mechanisms are involved in plastic deformation in the three deformation geometries. We explicitly identified the Burgers vectors of the dislocations as interatomic vectors in the structure of decagonal Al-Ni-Co.

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A Soft Ceramic Ti3SiC2 with Microscale Plasticity at Room Temperature

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.280-283.1343 ◽

2007 ◽

Vol 280-283 ◽

pp. 1343-1346 ◽

Cited By ~ 2

Author(s):

Shi Bo Li ◽

Hong Xiang Zhai

Keyword(s):

Plastic Deformation ◽

Surface Layer ◽

Acid Solution ◽

Basal Plane ◽

Room Temperature ◽

Damage Tolerance ◽

Stacking Faults ◽

Kink Band ◽

Band Formation ◽

Energy Absorbing

Microscale plasticity of Ti3SiC2 was investigated by Vickers hardness indentation. The surface layer of the hardness indentations was removed by acid solution to observe microstructure beneath the indentations, where a large number of bending, delamination and kinking grains were found. These features suggest that Ti3SiC2 is able to consume microdamage around the indentations. Numerous basal plane dislocations and stacking faults lying in Ti3SiC2 grains or accumulating at grain boundaries were observed. The basal plane dislocations play an important role in the microscale plastic deformation. The plasticity and damage tolerance for Ti3SiC2 at room temperature should be attributed to multiple energy absorbing mechanisms: grains bending, delamination, kink-band formation, and the basal plane slip, etc.

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Application of SEM-EBSD for Measurement of Plastic Strain Fields Associated With Weld Metal Hydrogen Assisted Cold Cracking

Volume 3: Materials and Joining ◽

10.1115/ipc2012-90388 ◽

2012 ◽

Author(s):

I. H. Brown ◽

W. L. Costin ◽

F. Barbaro ◽

R. Ghomashchi

Keyword(s):

Plastic Deformation ◽

Plastic Strain ◽

Weld Metal ◽

Cold Cracking ◽

Low Alloy Steels ◽

Plastic Strains ◽

Shielded Metal Arc Welding ◽

Electron Backscattered Diffraction ◽

Construction Time ◽

Girth Welds

The requirement for more efficient use of materials for pipelines has lead to the application of high strength low alloy steels such as X70 and X80 in pipelines. As the strength of these alloys has increased so has the risk of hydrogen assisted cold cracking (HACC). In Australia to minimize construction time, the root runs of girth welds are produced by shielded metal arc welding using cellulosic electrodes without either pre or post heating. Well defined welding criteria have been developed and are incorporated into the weld procedures for the elimination of HACC in the heat affected zone but the risk of cracking to the weld metal is still of concern. It has been reported that plastic deformation occurs prior to the formation of hydrogen cracks in weld metal. Therefore the evaluation of plastic strains at the micro- and nano-scale and their relationship to the weld metal microstructure could be of great significance in assessing the susceptibility of welds to weld metal hydrogen assisted cold cracking (WMHACC). A method for analysing plastic strains on the micro- and nano-scales using electron backscattered diffraction (EBSD) has been developed. This technique is based on the degradation and rotation of diffraction patterns as a result of crystallographic lattice distortion resulting from plastic deformation. The analysis can be automated to produce an Image Quality (IQ) map in order to relate the spatial distribution of plastic deformation to microstructural features e.g. grains or cracks. The development and assessment of techniques using Scanning Electron Microscopy (SEM) and EBSD for the determination of local plastic strain distribution in E8010 weld metal used for the root pass of X70 pipeline girth welds is discussed.

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Plastic Deformation in Microtomed Sections

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100066346 ◽

1971 ◽

Vol 29 ◽

pp. 458-459

Author(s):

J. Temple Black

Keyword(s):

Plastic Deformation ◽

Plastic Strain ◽

Applied Stress ◽

Elastic Strain ◽

High Strain ◽

Tool Material ◽

Cutting Edge ◽

Material Structure ◽

Geometrical Constraints

The output of the ultramicrotomy process with its high strain levels is dependent upon the input, ie., the nature of the material being machined. Apart from the geometrical constraints offered by the rake and clearance faces of the tool, each material is free to deform in whatever manner necessary to satisfy its material structure and interatomic constraints. Noncrystalline materials appear to survive the process undamaged when observed in the TEM. As has been demonstrated however microtomed plastics do in fact suffer damage to the top and bottom surfaces of the section regardless of the sharpness of the cutting edge or the tool material. The energy required to seperate the section from the block is not easily propogated through the section because the material is amorphous in nature and has no preferred crystalline planes upon which defects can move large distances to relieve the applied stress. Thus, the cutting stresses are supported elastically in the internal or bulk and plastically in the surfaces. The elastic strain can be recovered while the plastic strain is not reversible and will remain in the section after cutting is complete.

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Frequency Response of Fine Wire Thermocouples and Cold Wires over a Large Temperature Range in Airflows

Proceeding of Advanced Course in Measurement Techniques in Heat and MassTransfer ◽

10.1615/ichmt.1985.advcoursemeastechheatmasstransf.300 ◽

1985 ◽

Author(s):

C. Petit ◽

P. Gajan ◽

Pierre Paranthoen ◽

Jean-Claude Lecordier

Keyword(s):

Frequency Response ◽

Large Temperature ◽

Temperature Range ◽

Fine Wire

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Study on characteristics of schottky temperature detector based on metal/n-ZnO/n-Si structures

Micro and Nanosystems ◽

10.2174/1876402912999200910165426 ◽

2020 ◽

Vol 12 ◽

Author(s):

Fang Wang ◽

Jingkai Wei ◽

Caixia Guo ◽

Tao Ma ◽

Linqing Zhang ◽

...

Keyword(s):

High Temperature ◽

Temperature Measurement ◽

Temperature Response ◽

Large Temperature ◽

Mems Devices ◽

Temperature Range ◽

Response Characteristics ◽

High Temperature Measurement ◽

Temperature Detector ◽

Schottky Structure

Background: At present, the main problems of Micro-Electro-Mechanical Systems (MEMS) temperature detector focus on the narrow range of temperature detection, difficulty of the high temperature measurement. Besides, MEMS devices have different response characteristics for various surrounding temperature in the petrochemical and metallurgy application fields with high-temperature and harsh conditions. To evaluate the performance stability of the hightemperature MEMS devices, the real-time temperature measurement is necessary. Objective: A schottky temperature detector based on the metal/n-ZnO/n-Si structures is designed to measure high temperature (523~873K) for the high-temperature MEMS devices with large temperature range. Method: By using the finite element method (FEM), three different work function metals (Cu, Ni and Pt) contact with the n-ZnO are investigated to realize Schottky. At room temperature (298K) and high temperature (523~873K), the current densities with various bias voltages (J-V) are studied. Results: The simulation results show that the high temperature response power consumption of three schottky detectors of Cu, Ni and Pt decreases successively, which are 1.16 mW, 63.63 μW and 0.14 μW. The response temperature sensitivities of 6.35 μA/K, 0.78 μA/K, and 2.29 nA/K are achieved. Conclusion: The Cu/n-ZnO/n-Si schottky structure could be used as a high temperature detector (523~873K) for the hightemperature MEMS devices. It has a large temperature range (350K) and a high response sensitivity is 6.35 μA/K. Compared with traditional devices, the Cu/n-ZnO/n-Si Schottky structure based temperature detector has a low energy consumption of 1.16 mW, which has potential applications in the high-temperature measurement of the MEMS devices.

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