Models based on the relevant physical principles are a precondition to improve the understanding of microstructure-property relationships. Based on in-situ experiments the evolving microstructures can be subjected to a controlled thermo-mechanical treatment . The experimental results will be interpreted by means of thermodynamically based modeling in order to gain new insights about the underlying physics when designing new materials, see e.
Resume : Intermetallics are possible candidates for the substitution of CRM-containing materials in high-temperature applications as well as for the tools and parts loaded by mechanical wear. However, their disadvantage is low room-temperature ductility.
Materials under Extreme Loadings: Application to Penetration and Impact
This work brings the overview of the technologies, which can minimize this problem by refining the structure of the materials. The presented processes are mechanical alloying in combination with Spark Plasma Sintering and Self-propagating high-temperature synthesis. The mechanisms and advantages of these processes are shown on the examples of aluminide-based materials.
Resume : Nowadays, permanent magnets PMs have a wide set of applications in many industrial and technological fields, as large motors, generators, metallic elements separators. Currently, most of the PMs contain rare-earth RE elements, whose availability has become to decrease, and, as a consequence, their price has risen significantly, making these elements become critical on the European market.
Developing PMs without RE has become a very challenging task, in both scientific and technological field. Recently, many efforts are being performed towards the massive computational screening of new high-performance RE-free PMs.pricrolschala.gq
Materials under extreme conditions | The Keith Nelson Group
Although very accurate, the ab-initio calculations are computationally very demanding, thus, the exploration of structural phase is limited. In our study, we? Our goal is to devise a scheme combining both DFT calculations and Molecular Dynamics, in order to speed up the search of new materials with preserving its accuracy. We aim also to use these potentials to study some thermodynamic or structural properties of the new materials found by screening. Resume : The paper presents the influence of activation flux and shielding gas on tungsten inert gas abbr.
TIG welding of stainless steel. In the introduction part, duplex stainless steel was analysed. A-TIG process was explained and the possibility of welding stainless steels using A-TIG process to maximize productivity and the cost-effectiveness of welded structures was presented.
In the experimental part duplex stainless steel in thickness of 7 mm has been welded in butt joint. The influence of activation flux chemical composition upon the weld penetration has been investigated prior the welding. The welding process was performed by robot with TIG equipment. With selected welding technology preparation of plates and filler material containing Cr, Ni and Mn have been avoided. Specimens sectioned from the produced welds have been subjected to tensile strength test, microstructure analysis and corrosion resistance analysis.
A comparative study has determined ideal set of welding parameters for welding this type of stainless steels without edge preparation and addition of filler material containing critical raw materials as Cr, Ni and Mn.
Materials Under Extreme Loadings: Application to Penetration and Impact
Resume : High entropy alloys HEA represent a relatively new concept in material design. HEA are characterised by a high number of alloying elements, in unusually high proportion. Due to their specific particularities, high entropy alloys tend to form predominant solid solution structures that develop potentially high chemical, physical and mechanical properties, especially at elevated temperatures. High entropy alloys are usually compared with the superalloy family of materials. Among other elements Co is considered to be one of the main ingredients in superalloys.
Present paper is studying Co-less high entropy alloys with high potential in severe environment applications. The high entropy alloys based on Al-Cr-Fe-Mn-Ni system were prepared by induction melting and casting under protective atmosphere. The as-cast specimens were heat treated at various temperatures to determine the structure and property behaviour.
Samples taken before and after heat treatment were investigated for chemical, physical, structural and mechanical characteristics. Sigma phase composition and heat treatment parameters had major influence over the resulted alloy structure and properties. The HIP procedure causes hardening of the material and increase of density. The HIP is of great importance for superalloy castings due to the almost complete elimination of micro-porosity by a combination of plastic deformation, creep and diffusion.
However, during the HIP a carbide free zone and a contaminated surface layer are formed. The contaminated layer and carbide free zone has been studied on differently grinded P, P and polished samples made of superalloy IN The contaminated layer is consisted of oxides, carbides and nitrides formed due to the diffusion of chemical elements from metal matrix and their reaction with impurities in HIP atmosphere.
Finally, to conclude, in order to minimize loss of CRM alloying elements during HIP a smoother part surface is preferable. Many rechargeable batteries and highly efficient electric engines and generators contain REE compounds in their components. For example, they are used in hard disk drives, hybrid electric vehicles, wind mills or in everyday consumer products that content batteries such as mobile phones and lap-tops, industrial equipment?
Worldwide, due to the growing use of these products and technologies, it is forecast that REE world demand will soon exceed the supply. In Europe, the dependence on Chinese exports makes us extremely dependent and vulnerable, turning REE in one of the materials at highest supply risk. Nevertheless, existing recycling processes are based on hazardous solutions or processes which require very high energy consumption.
The targeted integrated solution is based on recently developed lab-proven technologies for direct high temperature electrolysis of REA production combined with an innovative and proven Ionic Liquid IL Extraction or tailored hydrometallurgical pre-treatment to demonstrate dramatic improvements in cost and environmental performance compared to state of the art technologies.
ILs could be a very promising alternative for the development of more efficient and environmentally friendly recycling processes, due to the fact that they can be fine-tuned to dissolve-extract selectively the desired metal or compound even at low temperatures? The proposed approach will determine the improvements in cost and environmental performance compared to state of the art technologies.
This will create new jobs, increase Europe? Resume : Among the critical raw materials CRMs used in tools for mechanical machining, tungsten and cobalt are massively used, as most of these tools are made of cemented carbide WC-Co. In a strategy to reduce the consumption of these CMRs, hard coatings can be deposited on the tool surface, so to increase their lifetime and optimize their performance. High Power Impulse Magnetron Sputtering HiPIMS is considered as a very useful film deposition technique allowing the realization of dense, hard and smooth coatings at high deposition rates.
Indeed, the high power density reached in the short pulses applied to the cathode material promotes the establishment of highly-ionized plasma, helping the deposition of high quality films. We deposited titanium aluminum nitride TiAlN films by means of the HiPIMS technique by changing the pulse duration at fixed voltage and average power, thus tuning the single pulse power.
X-ray diffraction XRD was conducted to study the evolution of the microstructural properties of the deposited films when changing the pulse duration, while scanning electron microscopy FE-SEM gave information about the influence of pulse length on film morphology. The film properties were then correlated to the film hardness obtained by means of nanoindentation measurements.
Resume : Tungsten is one of 14 materials identified by the European Commission as?
The aim of the work is to demonstrate application of DC plasma for production of spherical metal powders which is based on the use of waste materials, i. The proposed recycling process utilizes features of some metals which undergo reversible chemical reaction with oxygen. In contrast to metallic tungsten its trioxide is brittle and can be easily mechanically fragmented down to very fine powder.
The resulting irregular powder of the desired particle size distribution can be turned into metal by simple thermal treatment becoming feedstock for next step? The target spherical powder of desired particle size distribution can fabricated by proper handling of tungsten trioxide grinding, sieving, granulation and selection of speroidization parameters of reaction column equipped with FST 7MB plasma torch. The effects of electrical parameters of the plasma arc current, voltage , grain size of the starting powders, flow rate of the plasma gas and gas transporting the powder to the plasma stream on the final size and morphology after spheroidization process have been investigated.
The influence of hydrogen concentration in the plasma gas and flow of the carrier gas on the spheroidization degree, purity, chemical composition and powder specific surface area are shown. The single-layer oxides and respective multilayer structures have been deposited on glass substrates by successive DC magnetron sputtering using metallic targets in reactive for the oxide films or inert for the metallic interlayer films atmosphere. The wetting surface properties in function of time exposure at UV radiation nm have been also studied before and after heat treatments.
Main criteria of criticality? The most relevant environmental and economic impacts in the value chains are presented.
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Resume : The rapid technological development has caused the replace of old cathode ray tube equipment CRT with the most innovative liquid crystal displays LCD for several applications as personal computer monitors, laptops, tablet PCs, mobile phones, televisions. Considering their average lifetime, generally between 3 and 8 years, huge amount of these equipment inevitably reaches the end-of-life state and becomes a waste to manage. The interest for this kind of waste is due to the content of several materials, with different recovery potentials, that makes it a possible source of secondary raw material in the perspective of a circular economy.
More in detail, the main components of a typical LCD include: the panel, the frame and the electric and electronic parts, combined with the backlighting system that causes the classification of this WEEE as hazardous waste for the possible presence of fluorescent lamps with a mercury content. Nevertheless, particular attention should be given to the panel that includes an indium tin oxide film ITO , an optoelectronic material with specific characteristics of transparency to visible light, electric conduction and thermal reflection.
Indeed, this metal was included in the critical raw material list of by the European Commission, on the basis of supply risk and the possible impact connected with its mining. Currently, the whole indium on the market comes from a primary production, in particular as by-product of zinc mining and China is the largest supplier. The relevance of this metal is further confirmed by the European Substitutability index of 0. Nowadays, the LCD panel is disposed in landfilling sites for municipal waste, or stocked at the WEEE treatment plants, because no commercial recycling process is available yet.
This critical issue pushed the research towards the development of high efficiency indium recovery treatments to combine with the usual recycling of traditional fractions plastic, glass, cables, etc.