Zur Frage Supraleitung in σ-Phase Nb-Al / Superconductivity and σ-Phase Nb — Al

AbstractThe preparation and the alloy structure of Nb - Al samples containing σ.-phase are described. Using single-phase material it is shown that the o-phase Nb - Al, independent of composition and heat treatment, is not superconducting down to 1.3 K.

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Effect of MCl (M = Na, K) addition on microstructure and electrical conductivity of forsterite

The European Physical Journal Applied Physics ◽

10.1051/epjap/2020200161 ◽

2020 ◽

Vol 92 (1) ◽

pp. 10901

Author(s):

Saloua El Asri ◽

Hamid Ahamdane ◽

Lahoucine Hajji ◽

Mohamed El Hadri ◽

Moulay Ahmed El Idrissi Raghni ◽

...

Keyword(s):

Heat Treatment ◽

Electrical Conductivity ◽

Single Phase ◽

Sol Gel ◽

Complex Impedance ◽

Transmission Spectra ◽

Electrical Measurements ◽

Cation Type ◽

Edx Analyses ◽

The Fourier Transform

Forsterite single phase powder Mg2SiO4 was synthesized by sol–gel method alongside with heat treatment, using two different cation alkaline salts MCl as mineralizers (M = Na, K) with various mass percentages (2.5, 5, 7.5, and 10 wt.%). In this work, we report on the effect of the cation type and the added amount of used mineralizer on microstructure and electrical conductivity of Mg2SiO4. The formation of forsterite started at 680–740 °C and at 630–700 °C with KCl and NaCl respectively, as shown by TG-DTA and confirmed by XRD. Furthermore, the Fourier transform infrared (FTIR) transmission spectra indicated bands corresponding to vibrations of forsterite structure. The morphology and elemental composition of sintered ceramics were examined by SEM-EDX analyses, while their densities, which were measured by Archimedes method, increased with addition of both alkaline salts. The electrical measurements were performed by Complex Impedance Spectroscopy. The results showed that electrical conductivity increased with the addition of both mineralizers, which was higher for samples prepared with NaCl than those prepared with KCl.

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Coupling an organic photosensitizer and an inorganic framework into a single-phase material that shows visible-light photocurrent response

CrystEngComm ◽

10.1039/d0ce01685c ◽

2021 ◽

Author(s):

Tao Zhang ◽

Yue-Qiao Hu ◽

Qian-Wen Li ◽

Wei-Peng Chen ◽

Yan-Zhen Zheng

Keyword(s):

Visible Light ◽

Single Phase ◽

Photocurrent Response ◽

Inorganic Framework ◽

Single Phase Material

A rare hybrid of a 3D Sn–Se type framework and a ruthenium(ii) photosensitizer has been synthesized, and exhibits visible light photocurrent response.

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Effect of Ferrite Volume Fraction on Mechanical Properties of X80 Pipeline Steel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.989-994.212 ◽

2014 ◽

Vol 989-994 ◽

pp. 212-215

Author(s):

J. Liu ◽

G. Zhu ◽

W. Mao

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Work Hardening ◽

Single Phase ◽

Volume Fraction ◽

Pipeline Steel ◽

X80 Pipeline Steel ◽

Hardening Behavior ◽

Two Phases ◽

Better Than

The effect of volume fraction of ferrite on the mechanical properties including strength, plasticity and wok hardening was systematically investigated in X80 pipeline steel in order to improve the plasticity. The microstructures with different volume fraction of ferrite and bainite were obtained by heat-treatment processing and the mechanical properties were tested. The work hardening behavior was analyzed by C-J method. The results show that the small amount of ferrite could effectively improve the plasticity. The work hardening ability and the ratio of yield/tensile strength with two phases of ferrite/bainite would be obviously better than that with single phase of bainite. The improvement of plasticity could be attributed to the ferrite in which more plastic deformation was afforded.

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Sol-gel processing of cordierite: Effect of seeding and optimization of heat treatment

Journal of Materials Research ◽

10.1557/jmr.1990.1095 ◽

1990 ◽

Vol 5 (5) ◽

pp. 1095-1103 ◽

Cited By ~ 44

Author(s):

Ann M. Kazakos ◽

Sridhar Komarneni ◽

Rustum Roy

Keyword(s):

Heat Treatment ◽

Single Phase ◽

Excess Free Energy ◽

Sol Gel ◽

Nucleating Agents ◽

Optimum Conditions ◽

Nanosized Powders ◽

Nanocomposite Gels ◽

Powder Compacts ◽

Gel Processing

Three series of cordierite powders were prepared by the sol-gel route: a single phase (monophasic) gel prepared from alkoxides, a nominally triphasic nanocomposite gel made with two nanosized powders and one solution phase, and a truly compositionally triphasic nanocomposite gel prepared from three nanosized powders. Crystalline α-cordierite seeds were also incorporated with the gels and their effectiveness as nucleating agents was investigated and found to lower the crystallization temperature of α-cordierite by 125–150°C. The densification behavior of powder compacts was examined and alterations made to the heat treatment until optimum conditions were found. The truly triphasic compact sintered at 1300°C for 2 h resulted in 100% of theoretical density whereas the nominally triphasic and monophasis pellets densified to 96% and 80%, respectively. The enhanced densification achieved with powder compacct prepared for triphasic nanocomposite gels is due to part to the excess free energy of the three components.

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Heat treatememt effect on microstructure and mechanical properties of precipitation hardening elinvar alloy

Izvestiya vysshikh uchebnykh zavedenii. Fizika ◽

10.17223/00213411/64/5/68 ◽

2021 ◽

pp. 68-73

Author(s):

G.V. Shlyakhova ◽

◽

A.V. Bochkareva ◽

M.V. Nadezhkin ◽

◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Phase Composition ◽

Structural Analysis ◽

Thermal Treatment ◽

Precipitation Hardening ◽

Physical And Mechanical Properties ◽

Alloy Structure ◽

Treatment Mode ◽

Elinvar Alloy

This study presents experimental results of structural analysis, such as phase composition, grains size assessment, strength and hardness of Ni-SPAN-C alloy 902 after various heat treatment modes (hardening and aging for stress relaxation). A thermal treatment mode has been selected to obtain higher physical and mechanical properties of the elinvar alloy. It is shown that the improvement of the alloy structure in thermal treatment occurs due to the thermic stresses, as well as the formation and dissolution of intermetallides.

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Balance equations for a single-phase material

Modelling of Materials Processing - Materials Technology Series ◽

10.1007/978-1-4615-5813-2_3 ◽

1998 ◽

pp. 93-198

Author(s):

Gregory C. Stangle

Keyword(s):

Single Phase ◽

Balance Equations ◽

Single Phase Material

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Effect of Mo, V and Zr on the microstructure and mechanical properties of Ti2AlNb alloys

MATEC Web of Conferences ◽

10.1051/matecconf/202032108003 ◽

2020 ◽

Vol 321 ◽

pp. 08003

Author(s):

Yujun Du ◽

Xianghong Liu ◽

Jinshan Li ◽

Wenzhong Luo ◽

Yongsheng He ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Melting Process ◽

Phase Region ◽

Arc Furnace ◽

Micro Hardness ◽

Β Phase ◽

Before And After ◽

B2 Phase ◽

O Phase

Small button ingots of Ti2AlNb alloys with different contents of Mo, V and Zr were melted by vacuum non-consumable arc furnace. Due to the rapid cooling rate during melting process, only β grains without precipitation were observed in most of the button ingots and no regular phenomenon was found. However, when the samples were heated to β phase region and then furnace cooled to room temperate, different morphologies and quantities of primary α phase and second O phase formed from the β grains of different samples. It is suggested that the morphology of α phase was changed from lamellar to quadrilateral with increasing V and the lath O increased with increasing Zr. Besides, the residual β/B2 phase increased with increasing Mo and V. The EDS results showed that Al and Zr were enriched in α phase whereas Nb, Mo and V were enriched in β/B2 phase. The micro-hardness of these samples before and after heat treatment was detected and the micro-hardness increased with increasing Zr and decreasing Mo and V.

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Li-insertion Behavior in NanocrystallineTiO2-(MoO3)z Core-Shell Materials

MRS Proceedings ◽

10.1557/proc-658-gg10.4 ◽

2000 ◽

Vol 658 ◽

Author(s):

Gregory J. Moore ◽

Dominique Guyomard ◽

Scott H. Elder

Keyword(s):

Transition Metal ◽

Surface Charge ◽

Double Layer ◽

Single Phase ◽

Inductive Effect ◽

Core Shell ◽

Fundamental Study ◽

The Core ◽

Single Phase Material

ABSTRACTA fundamental study of the Li insertion behavior of a series of materials consisting of a TiO2 core having MoO3 on the surface has been carried out in order to determine the influence of the shell. These TiO2-(MoO3)z materials, where (z) denotes the fraction of coverage from a partial to a double layer, range in diameter from 40-100 Å. Calculations have been done on their theoretical lithium capacity using a maximum of Li0.5TiO2 for the core, and Li1.5MoO3 at the TiO2/MoO3 interface, and they have been compared to that found experimentally. The reversible Li-insertion capacity was shown to increase from 0.34 per Ti for the pure TiO2 sample, to 0.91 Li per transition metal when the MoO3 coverage increased to one monolayer. There was only one plateau observed in the electrochemical scans for the samples showing that they function as a single-phase material making them interesting for electrodes. The redox voltage of the TiO2/Li0.5TiO2 biphasic transformation increased 60 mV from the pure TiO2 to the sample containing one monolayer of MoO3. This effect was interpreted as due to a change in TiO2 surface charge coming from an inductive effect of Ti-O-Mo bonds.

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