Thermal stability of hydride phase obtained by mechanical treatment of Mg-10 mass% Fe in hydrogen under pressure

Heavy deformation plus micro alloying could be an effective way to obtain ultrafine grain structure of metals. In the present work, an Al-Cu-Mg alloy was microalloyed with Zr to obtain homogeneous precipitates and then heavily deformed by conventional forging at high temperature. The possible refining processing routes were studied and the superplasticity behaviors of the alloy was investigated. Results show that the micro alloyed alloy can be stably refined to 3-5μm under conventional processing routes. The Al-3Zr precipitates act both as additional sites to enhance recrystallization nucleation rate and pins to impede grain growth to increase the thermal stability of the fine grain structure. However, as the Al3Zr precipitates remains along grain boundaries, the superplastic capability of the material is not high. At 430°C with 1×10-4S-1 strain rate, the elongation obtained was 260%.

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The Influence of Complex Doping on Kinetics of Decomposition and Thermal Stability of Mg-Based Mechanical Alloys

Фізика і хімія твердого тіла ◽

10.15330/pcss.20.4.406-415 ◽

2019 ◽

Vol 20 (4) ◽

pp. 406-415

Author(s):

O.G. Ershova ◽

V.D. Dobrovolsky ◽

Yu.M. Solonin

Keyword(s):

Thermal Stability ◽

Thermal Desorption Spectroscopy ◽

Hydrogen Desorption ◽

Hydride Phase ◽

Hydrogen Storage Alloys ◽

Reactive Grinding ◽

Kinetics Of ◽

Reactive Mechanical Alloying ◽

Thermal Stability Of ◽

Complex Doping

Mechanical alloys (MАs) were synthesized by the method of reactive mechanical alloying. At a hydrogen pressure of 0.1 MPa, with the use of thermal desorption spectroscopy, the thermal stability, the kinetics of hydrogen desorption from the hydride phase MgH2 of the obtained MAs were studied. It has been established that the complex doping by of Fe, Si, Ti, leads to a significant improvement in the of hydrogen desorption from the hydride phase MgH2 of MA synthesized by the RMA. Hydrogen capacity CH of MА after reactive grinding for 20 h. was found to be equal to 5.7 % wt. Due to this alloying, the decrease in the thermodynamic stability of MgH2 is not established. The tested materials showed a high potential as hydrogen storage alloys especially for stationary application.

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Influence of the mechanical treatment on the structure and the thermal stability of alkaline-earth carbonates

Journal of Materials Science ◽

10.1023/b:jmsc.0000039208.65083.c7 ◽

2004 ◽

Vol 39 (16/17) ◽

pp. 5189-5193 ◽

Cited By ~ 14

Author(s):

J. M. Criado ◽

M. J. Diánez ◽

J. Morales

Keyword(s):

Thermal Stability ◽

Mechanical Treatment ◽

Alkaline Earth ◽

Thermal Stability Of

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Effects of high mechanical treatment and long-term annealing on crystal structure and thermal stability of Ti2O3 nanocrystals

RSC Advances ◽

10.1039/d0ra03862h ◽

2020 ◽

Vol 10 (43) ◽

pp. 25717-25720

Author(s):

Albina A. Valeeva ◽

Svetlana Z. Nazarova ◽

Hartmuth Schröttner ◽

Evgeny Yu. Gerasimov ◽

Andrey A. Rempel

Keyword(s):

Crystal Structure ◽

Thermal Stability ◽

Magnetic Susceptibility ◽

Mechanical Treatment ◽

High Energy ◽

High Energy Milling ◽

The Stability ◽

Thermal Stability Of

The effect of high-energy milling and long-term annealing on the stability of Ti2O3 nanocrystals was studied using a magnetic susceptibility method.

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The Ordered Phase Formation in Ti-Al-Ga Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100069193 ◽

1970 ◽

Vol 28 ◽

pp. 440-441

Author(s):

Shiro Fujishiro ◽

Harold L. Gegel

Keyword(s):

Thermal Stability ◽

High Temperature ◽

Titanium Alloys ◽

Growth Kinetics ◽

Stoichiometric Composition ◽

Good Potential ◽

Alpha Titanium ◽

Cold Rolled ◽

Kinetics Of ◽

Thermal Stability Of

Ordered-alpha titanium alloys having a DO19 type structure have good potential for high temperature (600°C) applications, due to the thermal stability of the ordered phase and the inherent resistance to recrystallization of these alloys. Five different Ti-Al-Ga alloys consisting of equal atomic percents of aluminum and gallium solute additions up to the stoichiometric composition, Ti3(Al, Ga), were used to study the growth kinetics of the ordered phase and the nature of its interface.The alloys were homogenized in the beta region in a vacuum of about 5×10-7 torr, furnace cooled; reheated in air to 50°C below the alpha transus for hot working. The alloys were subsequently acid cleaned, annealed in vacuo, and cold rolled to about. 050 inch prior to additional homogenization

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Microstructure studies of tungsten silicide schottky contacts on Gaas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100126445 ◽

1987 ◽

Vol 45 ◽

pp. 328-329

Author(s):

Yih-Cheng Shih ◽

E. L. Wilkie

Keyword(s):

Thermal Stability ◽

Field Effect Transistors ◽

Schottky Contact ◽

Schottky Contacts ◽

Excellent Thermal Stability ◽

Barrier Heights ◽

Gaas Substrates ◽

Film Adhesion ◽

Threshold Voltages ◽

Thermal Stability Of

Tungsten silicides (WSix) have been successfully used as the gate materials in self-aligned GaAs metal-semiconductor-field- effect transistors (MESFET). Thermal stability of the WSix/GaAs Schottky contact is of major concern since the n+ implanted source/drain regions must be annealed at high temperatures (∼ 800°C). WSi0.6 was considered the best composition to achieve good device performance due to its low stress and excellent thermal stability of the WSix/GaAs interface. The film adhesion and the uniformity in barrier heights and ideality factors of the WSi0.6 films have been improved by depositing a thin layer of pure W as the first layer on GaAs prior to WSi0.6 deposition. Recently WSi0.1 has been used successfully as the gate material in 1x10 μm GaAs FET's on the GaAs substrates which were sputter-cleaned prior to deposition. These GaAs FET's exhibited uniform threshold voltages across a 51 mm wafer with good film adhesion after annealing at 800°C for 10 min.

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