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Multiscale Copper-uDiamond Nanostructured Composites

Nanostructured copper-diamond composites can be tailored for thermal management applications at high temperature. A novel approach based on multiscale diamond dispersions is proposed for the production of this type of materials: a Cu-nDiamond composite produced by high-energy milling is used as a nanostructured matrix for further dispersion of micrometer sized diamond. The former offers strength and microstruct...

Elemental interdiffusion in W-Ta composites developed for fusion applications

Tungsten (W) was select for an extensive use in nuclear fusion devices due to its low neutron activation, high melting point and sputtering threshold as well as low hydrogen inventory. Nevertheless, W is brittle at low and moderate temperatures, which results in abnormal thermal stress, component fracture and extra erosion under reactor operation due to inherent thermal cycling events. An attractive way to solv...

Characterization of Cu2ZnSn(SSe)4 monograin powders by FE-SEM

The design and synthesis of high-efficiency materials to convert solar to electrical energy is an increasingly important research field. Within the photovoltaic technologies, crystalline Si have an 80% share while the remaining 20% are mostly thin film solar cells based on Cu(In,Ga)(S,Se)2 (CIGSSe) and CdTe [1,2]. However,the cost, the abundance and the environmental impact of the elemental components cannot be...

Blistering of W–Ta composites at different irradiation energies

Pure tungsten and tantalum plates and tungsten–tantalum composites produced via mechanical alloying and spark plasma sintering were bombarded with He+ and D+ energetic ion beams and deuterium plasmas. The aim of this experiment is to study the effects caused by individual helium and deuterium exposures and to evidence that the modifications induced in the composites at different irradiation energies could be fo...

Synergistic helium and deuterium blistering in tungsten–tantalum composites

Tungsten–tantalum composites with 10 and 20 at.% Ta were prepared by ball milling W powder with Ta fibers and by consolidating the milled materials with spark plasma sintering. The composites were implanted at room temperature with He+ (30 keV with a fluence 5 1021 at/m2) and/or D+ (15 keV with a fluence 5 x 1021 at/m2) ion beams. The materials were studied by scanning and high-resolution transmission electron ...

Effects of helium and deuterium irradiation on SPS sintered W–Ta composites at ...

Energetic He+ and D+ ions were implanted into different W–Ta composites in order to investigate their stability under helium and deuterium irradiation. The results were compared with morphological and chemical modifications arising from exposure of pure W and Ta. Special attention was given to tantalum hydride (Ta2H)formation due to its implications for tritium inventory. Three W–Ta composites with 10 and 20 at...

A brief summary of the progress on the EFDA tungsten materials program 

The long-term objective of the European Fusion Development Agreement (EFDA) fusion materials programme is to develop structural and armor materials in combination with the necessary production and fabrication technologies for reactor concepts beyond the International Thermonuclear Experimental Reactor. The programmatic roadmap is structured into four engineering research lines which comprise fabrication process...

NanoTiO2 e nanodiamante: aspectos relativos à caracterização e determinação da ...

Role of ogyxen and nitrogen in mechanical alloying mechanism of Ni-Ti powder mi...

In this study, the critical milling behaviour of Ni-Ti powder mixtures was evaluated in relation to the effect of atmospheric gases, more specifically to oxygen and nitrogen. Within the experimental conditions used, it is shown that both gases play an important role in the alloying process and that not only oxygen gas reacts with the mechanically alloyed powders but also nitrogen. The most effective mixing occu...

In situ experiments with synchrotron high-energy x-rays of Ni-Ti alloys produce...

The structural evolution that takes place during the homogenization heat treatments of powder metallurgical Ni-Ti- alloys was studied by in situ synchrotron diffraction. It is proposed to get a deeper understanding of this phenomenon by using different types of thermal/mechanical cycles.