Analysis of the Crystallogeometry of Tetragonal Martensite in Indium‒Cadmium Alloys by the Method of Electron Back-Scattering Diffraction

2019 ◽  
Vol 64 (5) ◽  
pp. 229-232
Author(s):  
V. M. Schastlivtsev ◽  
Yu. V. Khlebnikova ◽  
D. P. Rodionov ◽  
L. Yu. Egorova
Keyword(s):  
Back Scattering ◽  
Tetragonal Martensite

scholarly journals Analysis of the crystallogeometry of tetragonal martensite in indium-cadmium alloys by the method of electron back scattering diffractions

2019 ◽  
Vol 486 (1) ◽  
pp. 44-48
Author(s):  
V. M. Schastlivtsev ◽  
Yu. V. Khlebnikova ◽  
D. P. Rodionov ◽  
L. Yu. Egorova
Keyword(s):  
Building Blocks ◽  
Structural Level ◽  
Martensitic Plate ◽  
Back Scattering ◽  
Tetragonal Martensite

It was shown in the work using electron back scattering diffractions analysis that when cooling lower than temperature of the martensitic fcc-hct transformation in the alloy In - 4.5 wt% Cd a packet structure is formed consisting of colonies of tetragonal lamella plates. At the next packages there are always three grades of the plates of a tetragonal martensite which are in twinning situation and differing with the direction of the tetragonality axis. Each martensitic plate consists in turn of a set of more shallow submicrotwinning plates alternating in the direction of an axis of tetragonality. On the basis of the obtained data it is possible to conclude that the structure of the package consisting of twinning plates and the structure of the separate martensitic plate consisting, in turn, of submicro-twins submits to the general regularities. At each structural level in group of the neighboring areas the building blocks of three grades differing with the direction of a tetragonality axis are found.

Assessing the Power of Electron Back Scattering Diffraction Characterization of Deformed F-138 Steel from the View Point of Crystal Diffraction

2014 ◽  
Vol 51 (9) ◽  
pp. 634-655
Author(s):  
R. E. Bolmaro ◽  
M. C. Avalos ◽  
N. S. De Vincentis ◽  
A. M. Kliauga ◽  
H.-G. Brokmeier
Keyword(s):  
View Point ◽  
Back Scattering

APPLICATION OF ACOUSTIC METHODS IN RESEARCHES OF THE BOTTOM SEDIMENT DYNAMICS

2018 ◽  
Author(s):  
Б. Дивинский ◽  
B. Divinskiy ◽  
И. Грюне ◽  
I. Gryune ◽  
Р. Косьян ◽  
...  
Keyword(s):  
Suspended Sediment ◽  
Sediment Concentration ◽  
Irregular Waves ◽  
Single Frequency ◽  
Contactless Measurement ◽  
Measurement Means ◽  
Uniform Field ◽  
Wave Flume ◽  
Acoustic Methods ◽  
Back Scattering

Acoustic methods belong to contactless measurement means, possess high spatial and time resolution. Thus, the use of multifrequency allows directly profile both concentration and granulometric structure of the suspended substances. In 2008 in the Big Wave Flume (Hanover, Germany) by efforts of the Russian and German scientists there have been carried out the experiment on studying the bottom material suspension laws under the influence of irregular waves. The Aquascat 1000 acoustic back scattering sensor (ABS) manufactured by British company Aquatec (www.aquatecsubsea.com), equipped by a three-frequency transmitter with frequencies 1,0, 2,0 and 3,84 MHz, has been set on distance of 0,75 m from the bottom and 111 m from wave generator at the total depth of 3,2 m. Several dozen series of measurements at various parameters of surface waves have been carried out. The general picture of suspension is so that the external dynamic influence (currents, wave movements, turbulence, gravitation forces) creates a non-uniform field (gradient) of the suspended particles and in most cases due to this the average size of particles undergoes to the spatial-time variations. For this reason while defining the mass concentration of suspended sediment, using the single frequency transmitter there is necessity for numerous definition of the suspension granulometric structure what by isn’t always possible. If two and more frequencies are used the observed results comparison can give the information on average diameters of particles and on that basis the calculation of suspended sediment concentration is possibleLet's emphasize the basic advantages of back scattering acoustic gauges usage: – Obtaining the particles sizes and concentration distribution profiles is possible; – The initial granulometric structure of bottom sediments can be unknown (at use of several frequencies). The following can be referred to some lacks of the device: – The system should be calibrated in laboratory conditions; – In a positive feedback conditions the iterative computing process can converge to zero or to infinity. In this case experiments with a variation of carrier frequencies chosen for the analysis allow partially solve the problem (say experiments with different frequencies pairs, as 2/1 of MHz or 4/2 MHz).

Color Etching for Characterization the Grain Orientation in Spheroidal Graphite Cast Iron

2007 ◽  
Vol 537-538 ◽  
pp. 389-396 ◽  
Author(s):  
Ibolya Kardos ◽  
Zoltán Gácsi ◽  
Péter János Szabó
Keyword(s):  
Cast Iron ◽  
Crystallographic Orientation ◽  
Grain Orientation ◽  
Test Material ◽  
Spheroidal Graphite ◽  
Metallic Materials ◽  
Additional Information ◽  
Spheroidal Graphite Cast Iron ◽  
Graphite Cast Iron ◽  
Back Scattering

Color etching is a widely used technique for visualizing different phases in metallic materials. Its advantage to the traditional etching techniques is that it gives additional information within one phase, namely, the color shade of a given phase can change in a certain range. This paper demonstrates that, due to the physics of the color etching, the shade of a phase also depends on the crystallographic orientation of the investigated grain. As a test material, spheroidal graphite cast iron was used, and individual grain orientation was identified by automated electron back scattering diffraction (EBSD). Results showed that there is a strong correlation between grain orientation and the shades obtained by color etching.

Studies of inhomogeneous substances by ultrasonic back-scattering

1976 ◽  
Vol 2 (3) ◽  
pp. 195-198 ◽  
Author(s):  
B. Fay ◽  
K. Brendel ◽  
G. Ludwig
Keyword(s):  
Back Scattering

Thickness measurements by using back-scattering of gamma photons

2021 ◽  
Author(s):  
Rohit ◽  
Inderjeet Singh ◽  
B. Singh ◽  
B. S. Sandhu ◽  
A. D. Sabharwal
Keyword(s):  
Back Scattering ◽  
Thickness Measurements

scholarly journals A Ternary Map of Ni–Mn–Ga Heusler Alloys from Ab Initio Calculations

Metals ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 973
Author(s):  
Yulia Sokolovskaya ◽  
Olga Miroshkina ◽  
Danil Baigutlin ◽  
Vladimir Sokolovskiy ◽  
Mikhail Zagrebin ◽  
...  
Keyword(s):  
First Principles ◽  
Predictive Power ◽  
Computational Study ◽  
Heusler Alloys ◽  
Functional Materials ◽  
Ternary Diagram ◽  
Compositional Stability ◽  
Theoretical Predictions ◽  
Simultaneous Stability ◽  
Tetragonal Martensite

In the search for new magnetic functional materials, non-stoichiometric compounds remain a relatively unexplored territory. While experimentalists create new compositions looking for improved functional properties, their work is not guided by systematic theoretical predictions. Being designed for perfect periodic crystals, the majority of first-principles approaches struggle with the concept of a non-stoichiometric system. In this work, we attempt a systematic computational study of magnetic and structural properties of Ni–Mn–Ga, mapped onto ternary composition diagrams. Compositional stability was examined using the convex hull analysis. We show that the cubic austenite has its stability region close to the stoichiometric Ni2MnGa, in agreement with experimental data, while the tetragonal martensite spreads its stability over a wider range of Mn and Ni contents. The unstable compositions in both austenite and martensite states are located in the Ga-rich corner of the ternary diagram. We note that simultaneous stability of the austenite and martensite should be considered for potentially stable compounds suitable for synthesis. The majority of compounds are predicted to be ferrimagnetically ordered in both austenitic and martensitic states. The methodology used in this work is computationally tractable, yet it delivers some predictive power. For experimentalists who plan to synthesize stable Ni–Mn–Ga compounds with ferromagnetic order, we narrow the target compositional range substantially.

scholarly journals Spin–valley Hall phenomena driven by Van Hove singularities in blistered graphene

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
M. Umar Farooq ◽  
Arqum Hashmi ◽  
Tomoya Ono ◽  
Li Huang
Keyword(s):  
First Principles ◽  
Opposite Sign ◽  
Spin Splitting ◽  
First Principles Calculations ◽  
Van Hove Singularities ◽  
Spin Degree ◽  
Hall Effects ◽  
Back Scattering ◽  
Structural Deformations ◽  
Spin Momentum

AbstractUsing first-principles calculations, we investigate the possibility of realizing valley Hall effects (VHE) in blistered graphene sheets. We show that the Van Hove singularities (VHS) induced by structural deformations can give rise to interesting spin–valley Hall phenomena. The broken degeneracy of spin degree of freedom results in spin-filtered VH states and the valley conductivity have a Hall plateau of ±e2/2h, while the blistered structures with time-reversal symmetry show the VHE with the opposite sign of $$\sigma _{xy}^{K/K^{\prime}}$$ σ x y K / K ′ (e2/2h) in the two valleys. Remarkably, these results show that the distinguishable chiral valley pseudospin state can occur even in the presence of VHS induced spin splitting. The robust chiral spin–momentum textures in both massless and massive Dirac cones of the blistered systems indicate significant suppression of carrier back-scattering. Our study provides a different approach to realize spin-filtered and spin-valley contrasting Hall effects in graphene-based devices without any external field.

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