THE EFFECT OF THE MARTENSITIC TRANSFORMATION IN SODIUM ON THE THERMOELECTRIC POWER

1962 ◽  
Vol 40 (5) ◽  
pp. 550-556 ◽  
Author(s):  
J. Adler ◽  
S. B. Woods
Keyword(s):  
Crystal Structure ◽  
Martensitic Transformation ◽  
Thermoelectric Power ◽  
Electrical Resistance ◽  
Hexagonal Phase ◽  
Body Centered Cubic ◽  
Small Temperature ◽  
Experimental Apparatus ◽  
Electrical Resistance Measurements ◽  
Mixed Samples

When sodium is cooled, its crystal structure partially changes by martensitic transformation from body-centered cubic to close-packed hexagonal below about 40° K. Reversion does not begin until the temperature is raised above about 45° K, so there is a small temperature range in which sodium may consist of either pure body-centered cubic or mixed phases. Using results obtained by Dugdale and Gugan, it is possible to estimate the amount of hexagonal phase present in the mixed samples from electrical resistance measurements. We have measured the thermoelectric power at 43° K for specimens of body-centered cubic sodium and for partially transformed sodium whose composition was thus known. From these measurements the thermoelectric power of pure hexagonal sodium is estimated to be 10% smaller than that of cubic sodium at 43° K. The distribution of the phases in the partially transformed material is represented by two different models and this result is found to be insensitive to which is used. A brief description of the experimental apparatus is given and some theoretical implications of the results are considered.

High pressure thermoelectric power and electrical resistance measurements in WS2 single crystals

1995 ◽  
Vol 27/28 (2) ◽  
pp. 163-169 ◽  
Author(s):  
Ajay Agarwal ◽  
Sudeep Goyal ◽  
Mahendra Agarwal ◽  
Sudhir Vaidya ◽  
Chokalingam Karunakaran
Keyword(s):  
High Pressure ◽  
Single Crystals ◽  
Thermoelectric Power ◽  
Electrical Resistance ◽  
Electrical Resistance Measurements

Shape Memory Effect with Low Ms Thermoelastic thin Plate Martensite in an FE-33Ni-12CO-5Ti Alloy

1991 ◽  
Vol 246 ◽  
Author(s):  
Li Jian ◽  
C. C. Chou ◽  
C. M. Wayman
Keyword(s):  
Martensitic Transformation ◽  
Shape Memory ◽  
Liquid Nitrogen ◽  
Shape Memory Effect ◽  
Memory Effect ◽  
Thin Plate ◽  
Electrical Resistance ◽  
Plate Martensite ◽  
Electrical Resistance Measurements

AbstractAn Fe-33Ni-12Co-5Ti (wt.%) alloy was subjected to aging treatments to determine the effect of ausaging (at 700 °C for 5, 10 and 30 hr) on the martensitic transformation and shape memory effect. The Ms temperatures were determined by electrical resistance measurements and microstructures were examined by TEM. The shape memory was studied by bending specimens in liquid nitrogen and found to be associated with a low Ms thermoelastic thin plate martensite.

scholarly journals Effect of Recrystallization on β to α-Sn Allotropic Transition in 99.3Sn–0.7Cu wt. % Solder Alloy Inoculated with InSb

Materials ◽  
2020 ◽  
Vol 13 (4) ◽  
pp. 968
Author(s):  
Agata Skwarek ◽  
Balázs Illés ◽  
Tamás Hurtony ◽  
David Bušek ◽  
Karel Dušek
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Reference Material ◽  
Solder Alloy ◽  
Electrical Resistance ◽  
Transition Process ◽  
The Other ◽  
Electrical Resistance Measurements ◽  
Scanning Electron

The effect of recrystallization of 99.3Sn–0.7Cu wt. % solder alloy on the allotropic transition of β to α-Sn (so-called tin pest phenomenon) was investigated. Bulk samples were prepared, and an InSb inoculator was mechanically applied to their surfaces to enhance the transition. Half of the samples were used as the reference material and the other half were annealed at 180 °C for 72 h, which caused the recrystallization of the alloy. The samples were stored at −10 and −20 °C. The β-Sn to α-Sn transition was monitored using electrical resistance measurements. The expansion and separation of the tin grains during the β-Sn to α-Sn transition process were studied using scanning electron microscopy. The recrystallization of the alloy suppressed the tin pest phenomenon considerably since it decreased the number of defects in the crystal structure where heterogeneous nucleation of β-Sn to α-Sn transition could occur. In the case of InSb inoculation, the spreading of the transition towards the bulk was as fast as the spreading parallel to the surface of the sample.

Electrical resistance measurements on young balsam fir trees in relation to specific volume increment, foliar biomass, and ion content of bark and wood

1984 ◽  
Vol 14 (2) ◽  
pp. 177-180 ◽  
Author(s):  
H. Plene ◽  
R. G. Thompson ◽  
J. E. McIsaac ◽  
D. S. Fensom
Keyword(s):  
Electrical Resistance ◽  
Specific Volume ◽  
Balsam Fir ◽  
Ion Content ◽  
Volume Increment ◽  
Electrical Resistance Measurements ◽  
Foliar Biomass

Electrical resistance in young balsam fir (Abiesbalsamea (L.) Mill.) trees was inversely (nonlinear) correlated with specific volume increment, total foliar biomass, and the combined weight of the current and 1-year-old foliage. These relationships were stronger before budbreak than after. No relationship existed between concentrations of N, P, K, Ca, and Mg in the bark and wood collected around time of budbreak, and electrical resistance.

Rapid Thermal Transformation of A-15 Crystal Structure Metallic Thin Films

1995 ◽  
Vol 387 ◽  
Author(s):  
M. J. O'Keefe ◽  
C. L. Cerny
Keyword(s):  
Crystal Structure ◽  
Thin Films ◽  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Physical Vapor Deposition ◽  
Thermal Transformation ◽  
The Body ◽  
Cubic Phase ◽  
Body Centered Cubic ◽  
Body Center Cubic

AbstractPhysical vapor deposition of Group VI elements (Cr, Mo, W) can lead to the formation of a metastable A-15 crystal structure under certain processing conditions. Typically, a thermally induced transformation of the metastable A-15 structure into the equilibrium body centered cubic structure has been accomplished by conventional furnace annealing at T/Tm ≈ 0.3 from tens of minutes to several hours. In this study we report on the use of rapid thermal annealing to transform sputter deposited A- 15 crystal structure tungsten and chromium thin films into body centered cubic films within the same temperature range but at times on the order of one minute. The minimum annealing times and temperatures required for complete transformation of the A-15 phase into the BCC phase varied from sample to sample, indicating that the transformation was dependent on the film characteristics. The electrical resistivity of A-15 Cr and W films was measured before and after rapid thermal annealing and was found to significantly decrease after transformation into the body center cubic phase.

Textures of the Hot-Forged Ti6Al4V Alloy

2013 ◽  
Vol 203-204 ◽  
pp. 111-114
Author(s):  
Adam Bunsch ◽  
Wiktoria Ratuszek ◽  
Małgorzata Witkowska ◽  
Joanna Kowalska ◽  
Aneta Łukaszek-Sołek
Keyword(s):  
Deformation Temperature ◽  
Phase State ◽  
Hexagonal Phase ◽  
Ti6al4v Alloy ◽  
The Body ◽  
Cubic Phase ◽  
Body Centered Cubic ◽  
Two Phase ◽  
Different Temperatures

This paper presents the results of the texture investigation in the hexagonal phase and the body-centered cubic  phase of the Ti6Al4V alloy hot-deformed by forging. Forging was performed at two different temperatures on the occurrence of the single  and in the two-phase  +  state. It was found that after deformation both  and  phases are textured and their textures strongly depends on deformation temperature.

scholarly journals The influence of multifunctional microalloyed ceramics microstructure on its capacity properties

2018 ◽  
Vol 15 (2) ◽  
pp. 187-199
Author(s):  
Jelena Purenovic ◽  
Nedeljko Ducic ◽  
Branko Matovic ◽  
Milovan Purenovic
Keyword(s):  
Crystal Structure ◽  
Dielectric Constant ◽  
Electrical Properties ◽  
Electrical Resistance ◽  
Ceramic Materials ◽  
Porous Ceramics ◽  
Electrophysical Properties ◽  
Microstructural Properties ◽  
Structure Morphology ◽  
Composition Structure

Modified porous alumo-silicate ceramics, alloyed with magnesium and microalloyed with aluminum, belongs to modern multifunctional ceramic materials. Microalloying has led to important changes in dielectric and electrical properties of ceramics, such as dielectric constant and electrical resistance. These changes are conditioned by the microstructural properties of modified porous ceramics. The obtained results have shown the unity of the influence of composition, structure, morphology and application of microalloyed multifunctional alumosilicate ceramics on electrophysical properties. Microstructural investigations have shown that this type of ceramics has an amorphous-crystal structure, which causes important changes in its electrical properties and affects its activity. Therefore the ceramics can be considered as an active dielectric. A correlation between microstructural properties and structurally sensitive, i.e. electrophysical properties of microalloyed multifunctional alumo-silicate ceramics, was confirmed.

Crystal structure, thermoelectric power and superconductivity in La1.6 − xNd0.4SrxCuO4

1995 ◽  
Vol 213-214 ◽  
pp. 84-86 ◽  
Author(s):  
Y. Koike ◽  
A. Kobayashi ◽  
S. Takeuchi ◽  
S. Katano ◽  
S. Funahashi ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Thermoelectric Power
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