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Showing 1 to 20 of 21 for “"High Energy Ball Milling"”.
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Nanostructured Copper-Silver Alloys Synthesized by High Energy Ball Milling
… synthesized nanostructured alloys also display high hardness values, in the range of 4--6 Gpa. The hardness increases as milling temperature increase, as a result of phase separation and dynamic recrystallization.
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Sintering behavior of Ag-Sn alloys prepared via cryogenic high-energy ball milling
… of power-electronics, there is a need to develop high temperature die-attach materials that are mechanically stable at operating temperatures of 300◦C and provide excellent thermal conductivity between die and substrate materials. There are no obvious choices for all applications, however, low …
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In-situ Synthesis of Piezoelectric-Reinforced Metal Matrix Composites
… materials using reaction synthesis and high energy ball milling. Zinc oxide (ZnO) and barium titanate (BaTiO₃) have been successfully synthesized within copper and iron matrices in a range of volume percentages using reaction synthesis. The microstructures of these composites have been …
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Novel Synthesis of Bulk Nanocarbon (BNC)
… nanocarbon (BNC) material was synthesized using high energy ball milling and the carbonization of corn cob. Corn cob was mechanically milled for up to 20 hours by applying high energy ball milling to produce the milled powder. The milled powder was cold-compacted and carbonized at up to 1500°C to …
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Development of nanocrystalline Fe80Cr20 alloy using combination technique of ball milling and ultrasonic treatment for fuel cell interconnector
… The objective of this study is to explore the high energy ball milling (milled) combined with ultrasonic treatment (UT) in obtaining smaller crystallite size, finer surface morphology, higher thermal stability and more homogenous nanocrystalline Fe80Cr20 alloys. This condition was motivated by …
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Samarium strontium cobalt oxide – samarium doped ceria carbonate (SSC-SDCC) as a new potential composite cathode material for low temperature solid oxide fuel cell
… lower of area specific resistance (ASR) with high value of stability and porosity. This study focuses to investigate the correlation of powder composition and calcination temperature on the chemical compatibility, microstructures, physical, mechanical, thermal and electrochemical performance …
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Investigations of Ni-SDC carbonate (Ni-SDCC) as composite anode for low temperature solid oxide fuel cells
… (NC64), and 70:30 (NC73) were achieved using high-energy ball-milling. All powders were calcined at 600–800 °C, pelletized and sintered at 600 °C. Characterisation include the crystalline phases, thermogravimetry, thermal expansion coefficient (TEC), hardness and morphologies were conducted. …
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Severe plastic deformation in highly immiscible copper alloys: self-organization
… such as equal channel angular pressing (ECAP), high pressure torsion (HPT), high energy ball milling (BM), accumulative roll bonding (ARB), are well known to refine the microstructures of metals and alloys into non-equilibrium states with nanometer-size grains, and they are gaining widespread …
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Design of bulk nanocrystalline tungsten alloys via nano-phase separation sintering
… minority additions of chromium are produced by high-energy ball milling and then consolidated. Such alloys exhibit the onset of sintering at a very low temperature around 950 °C and a very rapid rate of densification. The mechanism of this accelerated sintering is established through …
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Shear induced mixing and self-organization in immiscible alloys during severe plastic deformation
… models. In this thesis, a combination of high energy ball milling (BM) and high pressure torsion (HPT) experiments are performed on a model Cu-Ag system between room temperature and 400 C at strain rates ranging from 0.1 to 6.25 s-1. Characterization of the shear induced mixing and …
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Enhancing stability of powder-route nanocrystalline tungsten-titanium via alloy thermodynamics
… materials to coarsen especially at the high temperatures required for processing. The structural instability stems from a large volume fraction of grain boundaries that carry an intrinsic energy penalty, but can be overcome by a consideration of the thermodynamics-based mechanism of …
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Designing Microstructure through Reverse Peritectoid Phase Transformation in Ni₃Mo Alloy
High-energy ball milling and powder metallurgy methods were used to produce a partially alloyed nickel and molybdenum of γ-Ni₃Mo composition (Ni-25at.%Mo). Milled powders were cold-compacted, sintered/solutionized at 1300°C for 100h sintering followed by quenching. Three transformation studies were …
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Direct 3D and in situ characterization of light metal hydrides for hydrogen storage
… generated interest in hydrogen as a sustainable energy carrier. Developing effective hydrogen storage for automotive applications is a central challenge in realizing a hydrogen energy economy. Light metal hydrides possess high storage capacities, but sluggish hydrogen uptake and release kinetics …
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The superconducting properties, composition and microstructure of nanocrystalline $A15\ \textnormal{Nb}_{3}(\textnormal{Al}_{1-x}\textnormal{Ge}_{x})$ superconductors for high magnetic field applications
… superconductors with 0 ≤ x ≤ 1. High-energy ball milling was used to produce disordered nanocrystalline powders from binary compounds and from pure elemental powders. A detailed analysis of powders milled for up to 30 h was performed using X-ray diffraction, differential scanning …
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Calcium oxide-based sorbents for CO2 capture at high temperature
… gasification combined cycle (IGCC) design. High concentrations of CO2 and elevated operating pressures/temperatures reduce the energy requirements of this process to 10-16%, which is roughly half that for post-combustion CO2 capture.[1] CaO has emerged as an attractive material to integrate …
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Rhenium, osmium and iridium diborides by mechanochemistry: Synthesis, structure, thermal stability and mechanical properties
… studied. ReB2 was recently reported to exhibit high hardness and low compressibility, which both are strong functions of its stoichiometry, namely Re to B ratio. Most of the techniques used for ReB2 synthesis reported 1:2.5 Re to B ratio because of the loss of the B during high temperature …
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Modifying burning rate and agglomeration size in aluminized composite solid propellants using mechanically activated metals
… and it is known for its ease of ignition and high oxidation energy content. It has been used as a metal fuel to increase burning rates of composite modified double base (CMDB) and ammonium perchlorate (AP) composite propellants. However, the ignition temperature is larger than the comparable …
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Thermal Stability, Microstructures and Mechanical Properties of Nanostructured/Ultrafine Structured Cu-5vol.%Al₂O₃ Nanocomposites Fabricated by High Energy Mechanical Milling and Powder Compact Extrusion
… aspect, ultrafine structured MMNCs have a higher room temperature strength and better high temperature performance due to grain boundary strengthening, nanoparticle strengthening and Zener pinning effects compared to their metal matrices. On the scientific aspect, there is the question of …
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Atomic Modelling of Disorder in Metal Nanocrystals
… of nanocrystals observed in powders produced by high-energy ball milling, which is also a topic discussed in (ii). The work aims to show a general approach to atomistic modelling, both for isolated nanoparticles with definite shapes, and grains of unspecified shape in plastically deformed …
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