A Novel Method to Significantly Improve the Mechanical Properties of n-Type Bi(1−x)Sbx Thermoelectrics Due to Plastic Deformation

A unique method was developed to significantly improve the strength of Bi(1−x)Sbx single crystals, the most effective thermoelectric (TE) materials in the temperature range from 100 to 200 K due to their plastic deformation by extrusion. After plastic deformation at room temperature under all-round hydrostatic compression in a liquid medium, n-type Bi–Sb polycrystalline solid solutions show a significant increase in mechanical strength compared to Bi–Sb single crystals in the temperature range from 300 to 80 K. The significantly higher strength of extruded alloys in comparison with Bi–Sb single crystals is associated with the development of numerous grains with a high boundary surface as well as structural defects, such as dislocations, that accumulate at grain boundaries. Significant stability of the structure of extruded samples is achieved due to the uniformity of crystal plastic deformation under all-round hydrostatic compression and the formation of the polycrystalline structure consisting of grains with the orientation of the main crystallographic directions close to the original single crystal. The strengthening of Bi–Sb single crystals after plastic deformation allows for the first time to create workable TE devices that cannot be created on the basis of single crystals that have excellent TE properties, but low strength.

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X-RAY-IRRADIATED KTiOPO4: ESR STUDIES

Modern Physics Letters B ◽

10.1142/s0217984992000223 ◽

1992 ◽

Vol 06 (03) ◽

pp. 177-181 ◽

Cited By ~ 17

Author(s):

BORIS V. ANDREEV ◽

VLADIMIR N. EFIMOV

Keyword(s):

Single Crystals ◽

Room Temperature ◽

X Ray ◽

Temperature Range ◽

First Time ◽

Paramagnetic Centres

The study of radiation paramagnetic centres (RPC) arising in flux-grown KTiOPO 4 (KTP) single crystals at X-ray-irradiation at 300 K was conducted by the ESR-method in the temperature range of 3.7÷300 K . For the first time in X-ray-irradiated KTP there were found electron and hole RPC stable at room temperature and related to Ti 3+ and Al 3+ impurity, respectively.

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Weak ferromagnetic response in PbZr1−xTixO3 single crystals

Journal of Materials Chemistry C ◽

10.1039/c9tc03710a ◽

2019 ◽

Vol 7 (36) ◽

pp. 11085-11089

Author(s):

Iwona Lazar ◽

Monika Oboz ◽

Jerzy Kubacki ◽

Andrzej Majchrowski ◽

Julita Piecha ◽

...

Keyword(s):

Hysteresis Loop ◽

Single Crystals ◽

Room Temperature ◽

Ferromagnetic Hysteresis ◽

First Time ◽

Ferromagnetic Hysteresis Loop ◽

Weak Ferromagnetic

For the first time, a weak ferromagnetic hysteresis loop at room temperature has been observed in PbZr1−xTixO3 (PZT) single crystals.

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PSEUDO-GAP FEATURES OF INTRINSIC TUNNELING IN (HgBr2)-Bi2212 SINGLE CRYSTALS

International Journal of Modern Physics B ◽

10.1142/s0217979299003878 ◽

1999 ◽

Vol 13 (29n31) ◽

pp. 3758-3763 ◽

Cited By ~ 54

Author(s):

AUGUST YURGENS ◽

DAG WINKLER ◽

TORD CLAESON ◽

SEONG-JU HWANG ◽

JIN-HO CHOY

Keyword(s):

Temperature Dependence ◽

Single Crystals ◽

Room Temperature ◽

Unit Cell ◽

Superconducting Gap ◽

Axis Direction ◽

Temperature Range ◽

Dynamic Conductance

The c-axis tunneling properties of both pristine Bi2212 and its HgBr 2 intercalate have been measured in the temperature range 4.2-250 K. Lithographically patterned 7-10 unit-cell heigh mesa structures on the surfaces of these single crystals were investigated. Clear SIS-like tunneling curves for current applied in the c-axis direction have been observed. The dynamic conductance d I/ d V(V) shows both sharp peaks corresponding to a superconducting gap edge and a dip feature beyond the gap, followed by a wide maximum, which persists up to a room temperature. Shape of the temperature dependence of the c-axis resistance does not change after the intercalation suggesting that a coupling between CuO 2-bilayers has little effect on the pseudogap.

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Plastic Deformation of Mo(Si,Al)2 Single Crystals with the C40 Structure

MRS Proceedings ◽

10.1557/proc-460-605 ◽

1996 ◽

Vol 460 ◽

Author(s):

M. Moriwaki ◽

K. Ito ◽

H. Inui ◽

M. Yamaguchi

Keyword(s):

Single Crystals ◽

Deformation Behavior ◽

Basal Slip ◽

Room Temperature ◽

Slip Systems ◽

Temperature Range ◽

Al Content ◽

Partial Dislocations ◽

Increasing Temperature ◽

Critical Resolved Shear Stress

ABSTRACTThe deformation behavior of single crystals of Mo(Si,Al)2 with the C40 structure has been studied as a function of crystal orientation and Al content in the temperature range from room temperature to 1500°C in compression. Plastic flow is possible only above 1100°C for orientations where slip along <1120> on (0001) is operative and no other slip systems are observed over whole temperature range investigated. The critical resolved shear stress for basal slip decreases rapidly with increasing temperature and the Schmid law is valid. Basal slip appears to occur through a synchroshear mechanism, in which a-dislocations (b=1/3<1120>) dissociate into two synchro-partial dislocations with the identical Burgers vector(b*1/6<1120>) and each synchro-partial further dissociates into two partials on two adjacent planes.

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Plastic deformation of single crystals of a DO19compound with an off-stoichiometric composition (Ti-36·5 at.% Al) at room temperature

Philosophical Magazine A ◽

10.1080/01418619308225357 ◽

1993 ◽

Vol 67 (6) ◽

pp. 1315-1332 ◽

Cited By ~ 87

Author(s):

H. Inui ◽

Y. Toda ◽

M. Yamaguchi

Keyword(s):

Plastic Deformation ◽

Single Crystals ◽

Room Temperature ◽

Stoichiometric Composition

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Plastic Deformations in L10-Ordered Single Crystals with their c/a Ratios Less than Unity

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.459 ◽

2007 ◽

Vol 561-565 ◽

pp. 459-462

Author(s):

Katsushi Tanaka ◽

Hiromitsu Ide ◽

Yoshinori Sumi ◽

Kyosuke Kishida ◽

Haruyuki Inui

Keyword(s):

Shear Stress ◽

Temperature Dependence ◽

Single Crystals ◽

Room Temperature ◽

The Other ◽

Compressive Deformation ◽

Positive Temperature ◽

Plastic Deformations ◽

Temperature Range ◽

Critical Resolved Shear Stress

Compressive deformation of L10-ordered single crystals of FePd whose c/a ratio less than unity have been investigated from room temperature to 823 K. The results show that the critical resolved shear stress (CRSS) for octahedral glide of ordinary dislocations is smaller than that of super-lattice dislocations in all the temperature range investigated, that is the opposite sense to the case of Ti-56 mol% Al. The CRSS for ordinary dislocations virtually independent to the temperature. On the other hand, the CRSS for super dislocations exhibits a weak positive temperature dependence from room temperature up to 573 K and decreases in higher temperatures.

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Structure Characteristics of Cubic and Orthorhombic Phases of High Density Scintillator Pbf2 from 4.2–300 K

MRS Proceedings ◽

10.1557/proc-348-143 ◽

1994 ◽

Vol 348 ◽

Author(s):

Ivan Shmyt'ko ◽

I.B. Savchenko ◽

N.V. Klassen ◽

B.Sh. Bagautdinov ◽

G.A. Emel'chenko ◽

...

Keyword(s):

Phase Transition ◽

Plastic Deformation ◽

Temperature Dependence ◽

Single Crystals ◽

Room Temperature ◽

Cell Parameter ◽

Structure Characteristics ◽

Pseudocubic Phase ◽

Bulk Single Crystals ◽

Structural Aspects

ABSTRACTAn anomaly of the temperature dependence of the unit cell parameter has been observed for β–PbF2 single crystals at 200 K that is interpreted as a phase transition to a pseudocubic lattice. Such a pseudocubic phase is observable at room temperature after uniaxial plastic deformation of the bulk single crystals. The structural aspects of the β→α transition have been established. The as-grown crystals of α–PbF2 phase are shown to undergo a phase transition at 100 K.

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Peculiarities of pseudogap in Y0.95Pr0.05Ba2Cu3O7−δ single crystals under pressure up to 1.7 GPa

Scientific Reports ◽

10.1038/s41598-019-55959-1 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 7

Author(s):

A. L. Solovjov ◽

L. V. Omelchenko ◽

E. V. Petrenko ◽

R. V. Vovk ◽

V. V. Khotkevych ◽

...

Keyword(s):

Critical Temperature ◽

Hydrostatic Pressure ◽

Single Crystal ◽

Single Crystals ◽

Temperature Interval ◽

Fluctuation Theory ◽

Structural Defects ◽

Fluctuation Conductivity ◽

First Time ◽

Effect Of Hydrostatic Pressure

AbstractThe effect of hydrostatic pressure up to P = 1.7 GPa on the fluctuation conductivity σ′(T) and pseudogap ∆*(T) in Y0.95Pr0.05Ba2Cu3O7−δ single crystal with critical temperature Тс = 85.2 K (at P = 0) was investigated. The application of pressure leads to the increase in Tc with dTc/dP = +1.82 K∙GPa−1 while the resistance decreases as dlnρ(100 K)/dP = −(10.5 ± 0.2) %∙GPa−1. Regardless of the pressure, in the temperature interval from Tc to T0 (~88 K at P = 0) the behaviour of σ′(T) is well described by the Aslamazov – Larkin (AL – 3D) fluctuation theory, and above the T0 by the Lawrence – Doniach theory (LD). The Maki-Thompson (MT – 2D) fluctuation contribution is not observed. This indicates the presence of structural defects in the sample induced by Pr. Here it is determined for the first time that when the pressure is applied to the Y1−xPrxBa2Cu3O7−δ single crystal, the pseudogap increases as dlnΔ*/dP = 0.17 GPa–1.

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Dislocation Structures in Deformed Tin Single Crystals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054790 ◽

1982 ◽

Vol 40 ◽

pp. 468-469

Author(s):

G.W. Qiao

Keyword(s):

Plastic Deformation ◽

Electron Beam ◽

Low Temperature ◽

Single Crystals ◽

Current Density ◽

Perchloric Acid ◽

Room Temperature ◽

High Mobility ◽

Tetragonal Structure ◽

Methanol Mixture

Although β-tin is a familiar metal with tetragonal structure, its dislocation structures in bulk specimens after plastic deformation or irradiation have not been reported with observations by TEM probably because of difficulties in preparing specimens and the relatively high mobility of dislocations under electron beam illumination at room temperature (T/Tm~0.7). It proved possible to prepare specimens of β-tin for TEM observation using low temperature, double-jet electro-polishing techniques using 8% perchloric acid in methanol mixture at -30 °C under 80 volts and a typical current density of 0.7 Acm-2.

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Ionic Conductivity of Li2ZnTi3O8 Single Crystal

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.497.26 ◽

2011 ◽

Vol 497 ◽

pp. 26-30 ◽

Cited By ~ 1

Author(s):

Shinichi Furusawa ◽

Hiroshi Ochiai ◽

Khoji Murayama

Keyword(s):

Ionic Conductivity ◽

Single Crystal ◽

Temperature Dependence ◽

Single Crystals ◽

Powder Diffraction ◽

Floating Zone ◽

Zinc Titanate ◽

X Ray ◽

Temperature Range ◽

First Time

Single crystals of lithium zinc titanate (Li2ZnTi3O8) were grown in a double-mirror type optical floating-zone furnace for the first time. Single crystals were characterized by X-ray powder diffraction and Laue measurements. The ionic conductivity of the single crystals was measured in the temperature range of 400–700 K. Below 600 K, the ionic conductivity of the single crystal is one to two orders of magnitude higher than that of polycrystalline Li2ZnTi3O8. In the temperature range of 550–600 K, the temperature dependence of the ionic conductivity shows non-Arrhenius behaviour.

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