15th International Ceramics Congress
Poster Presentations


C:P01  Silicon Powder Recovery: From End-of-Life Photovoltaic Panels to Si-SiC Composites
S. Grilli, E. Salernitano, M. Scafè, F. Burgio, P. Fabbri, G. Magnani, ENEA SSPT-PROMAS-TEMAF, Laboratory of Materials Technologies Faenza, Faenza (RA), Italy

In recent years, the photovoltaic (PV) sector has remarkably grown and the related market was dominated in particular by silicon PV panels. In the context of circular economy, the management of huge amount of End-of-Life Si-based solar cells also concerns the recovery of valuable metals, including Si as Critical Raw Material. A current research topic is the Si recovery by chemical, mechanical, thermal or combined processes, for several industrial sectors, as the automotive. One of the most used pre-treatment for the recycle of Si-based solar cells consists of separating the plastic components, followed by grinding to achieve three different fractions of materials: glass particles, ethyl-vinyl acetate agglomerates and a non-glassy fraction containing the optically active material (Si) incorporated into polymeric layers. In this work the scraps from the non-glassy fraction were first pyrolyzed to remove the polymeric residues, then the obtained Si-containing powder was characterized by TGA and finally used for the production of Si-SiC composites by pressureless infiltration of porous SiC preforms. The morphology of the obtained composites was observed by SEM, the semiquantitative analysis was carried out by EDS and the mechanical strength was measured by four point bending test.

C:P02  Grain Boundary Mobility of Alumina as a Function of Varying Dopant Concentrations
y. shalabi, R. Marder, W.D. Kaplan, Technion- Israel Institute of Technology, Iksal, Israel

An important microstructural feature of polycrystalline materials is grain size since it affects mechanical and functional properties. One of the most studied ceramic materials is α-alumina (α-Al2O3), which has served as a paradigm for the study of grain growth and is important for technological applications. Many studies showed that dopants and/or impurities can cause significant changes to the grain boundary mobility of materials. This can occur by equilibrium (Gibbsian) segregation of solutes to grain boundaries, which is driven by a reduction in grain boundary energy. The segregated solutes then induce solute-drag or solute-acceleration, changing the grain boundary mobility and how the microstructure evolves. Alternatively, above the solubility limit, dopants and/or impurities can result in precipitation of secondary phases, which either reduce grain boundary mobility by Zener drag, or accelerate mobility by the formation of liquid phases. In this study the grain size as a function of annealing time (at 1600°C) was used to extract the effective grain boundary mobility for undoped polycrystalline alumina and alumina doped with Cr. Cr is fully soluble in alumina, so the correlation between solute activity, solute adsorption, and solute-drag/acceleration can be characterized.

C:P03  The Influence of Anorthite Glass on Grain Boundary Mobility in Alumina
n. fabri1, R. Marder1, R. Rovai2, W.D. Kaplan1, 1Department of Materials Science and Engineering, Technion - Israel Institute of Technology, Haifa, Israel; 2Industrie Bitossi S.P.A., Vinci, Italy

It is well known that dopants and/or impurities can cause significant changes to the grain boundary mobility of materials. This can occur by equilibrium (Gibbsian) segregation of solutes to grain boundaries, driven by a reduction in grain boundary energy, and resulting in solute-drag or solute-acceleration. Alternatively, above the solubility limit, dopants and/or impurities can result in precipitation of secondary phases, which either reduce grain boundary mobility by Zener drag, or accelerate mobility by the formation of liquid phases. The influence of a grain boundary wetting film versus an adsorbate on alumina grain mobility is unknown. Anorthite glass is a common impurity phase in commercial alumina, and sometimes even added on purpose to improve densification. The present study focuses on the influence of anorthite glass on grain growth of alumina while also studying the influence of the annealing atmosphere (air, He, or vacuum) on grain boundary mobility and the composition at grain boundaries and triple junctions.

C:P04  Glass Injection Moulding; Investigation of the Complete Process Chain for a Commercial Glass Powder
M. Zürn, T. Hanemann, Karlsruhe Institute of Technology, Institute for Applied Materials, Eggenstein - Leopoldshafen, Germany

In recent years, powder injection moulding has become an increasingly attractive process for the production of structured components. Powder injection moulding is mostly treated with metals and ceramics. In this work, the complete process chain from the production of the feedstock to the final sintering for powder injection moulding was extended to a commercial glass powder. First, it is necessary to develop a feedstock suitable for replication. In this case, a round fused silica was used in conjunction with various binder systems, e.g. polyethylene glycol, polyvinyl butyral and stearic acid, to produce initial test structures by injection moulding. Subsequently, debinding and sintering processes were developed and, after improvement of these, fully dense, translucent to nearly transparent test specimens were produced. It was shown that, in addition to the binder system, the debinding and sintering conditions also have a major influence on the final product. For example, sintering under vacuum conditions instead of atmosphere enabled the dimensional stability of the final product to be achieved. In summary, the entire process chain of manufacturing glass components by injection moulding was successfully demonstrated.

C:P06  Laser Ablation Behavior of B4C-Cf-GNPs Hybride High-temperature Composites Sintered by Spark Plasma Sintering
P. Hvizdoš, V. Puchý, Institute of Materials Research, Slovak Academy of Sciences, Košice, Slovakia

B4C ceramics are interesting for low weight and high temperature applications. The addition of carbon fibers (CF) and graphene aims to reduce the density and modify the properties. Cf and GNP reinforced B4C matrix composites were fabricated by SPS. The ablation and oxidation of B4C-based hybride high-temperature composites with 30 vol% Cf and 0.5 wt% GNPs with SiC and TiB2 sintering additives were tested under different exposition times in a high power infrared laser station to observe the difference in ablation. Microstructure of the prepared materials was studied by electron and light microscopies, their mechanical properties of the composites were evaluated by (nano) indentation methods. Fibers provided non-catastrophic fracture behavior of the composites as evidenced by the stress-displacement curves and fracture surface of the composites. Interdiffusion transition regions formed between Cf, GNPs and B4C matrix under high sintering temperature, which were responsible for the balanced strength and ductility of the composites. The addition of carbon fibers and graphene nanoplatelets results in smaller crack sizes indicating an improvement in fracture toughness.

C:P07  Cool-SPS: From Classic Ferroelectrics to Transparent Ceramics?
F. MOLINARI, V. Mary, A. Zudas, C. Sanz, A. Fargues, U-C. Chung, M. Josse, CNRS, Univ. Bordeaux, Bordeaux INP, ICMCB, UMR 5026, Pessac, France

The Cool-SPS (Spark Plasma Sintering) approach relies on chemical reactivity and high pressures (40-900MPa) for the processing of ceramics at low temperatures (<600°C). It involves multidimensional adjustment of these experimental parameters making Cool-SPS an extremely versatile approach with regard to the various type of materials that can be processed and the range of processing conditions. This variety is now illustrated by different studies including the sintering of: thermodynamically fragile materials, molecular ceramics [1] or even refractory oxides [2]. In this communication, it will also be shown that Cool-SPS can be used to obtain ceramics of the classic ferroic materials that are Rochelle salt, KDP, ADP, and TGS. Moreover, recent work extended the possibilities offered by Cool-SPS, highlighting a potential new field of application: transparent ceramics. This communication will illustrate the possibility to obtain translucent ceramics at low temperature.
[1] T. Hérisson de Beauvoir et al, (a) J. Mater. Chem. C., 2018, 6, 2229. (b) Solid State Sciences, 2020, 102, 106171. (c) Dalton Transactions, 2020, 49(23), 7820-7828. (d) J. Eur. Ceram. Soc., 2018, 38(11), 3867. (e) Ceram. Int., 2019, 45(7B), 9674. [2] C. Elissalde et al, Scripta Mater., 2019, 168, 134

C:P08  Vat Photopolymerization 3D Printing of Scaffold Structures Mimetic to Bone using Prepared Bovine Hydroxyapatite
R. ERBERELI¹, I.L. de Camargo1, 2, C.A. Fortulan1, 1Department of Mechanical Engineering, School of Engineering of São Carlos, University of São Paulo, São Carlos, SP, Brazil; 2Federal Institute of Education, Science and Technology of São Paulo, Itaquaquecetuba, SP, Brazil

Hydroxyapatite (HA) is one of the most used materials as a bone substitute or repair. Its application as a scaffold can promote osseointegration when having a geometry similar to the bone defect. However, it is necessary to use manufacturing technologies that promote parts with high controlled porosity, and mechanical strength to assist the osteoconductivity of the scaffold in the early stages of bone recovery. This work aims to produce high-performance bioceramics scaffolds that mimic the bone trabecular structure using prepared bovine HA as raw material and vat photopolymerization additive manufacturing. For that, the phase composition of the obtained HA and a commercial one were compared via X-ray diffraction. Also, photosensitive ceramic slurries were developed and their rheological behavior and stability were analyzed. Microtomography provided 3D models of bovine bones, which were used to produce trabecular bone mimetic pieces by additive manufacturing. These parts were debound and sintered, and their density was measured using the Archimedes principle. The hydroxyapatite of bovine origin, an economical material, proved to be an adequate raw material for the additive manufacturing of parts for customized bone implants.

C:P09  Microwave-assisted Hydrothermal Synthesis of Doped Titanium Dioxide Quantum Dots and its Application in Photocatalysis
M. Sagrilo Frizzo1, K. Betega2, C.M. Poffo1, D. Hotza1, 2, J.B. Rodrigues Neto1, 1Graduate Program in Materials Science and Engineering (PGMAT), Federal University of Santa Catarina (UFSC); 2Department of Chemical Engineering (EQA), Laboratory of Processing of Ceramics (PROCER), Federal University of Santa Catarina (UFSC), Florianopolis, Brazil

In this work, TiO2 quantum dots (QDs) were synthesized and evaluated as photocatalysts for the degradation of RR141 azo dye and tetracycline antibiotics. QDs were obtained by a microwave-assisted method. Different microwave times (10 up to 60 min) and temperatures (120 up to 180 °C) were used. Raman and XRD data detected anatase as the major crystalline phase. XRD also indicated an increase in the interfacial component with microwave temperature decreases, resulting in super adsorptive QDs. TiO2 crystallites presented a mean size of ~5 nm as calculated from XRD spectra and confirmed by TEM micrographs. QDs presented a large specific surface area (~290 m2·g-1), a high adsorption capacity, and a fast 100% degradation of RR141 using UV-B wavelength. In order to increase the interfacial component fraction and improve the adsorptive property and bandgap of the QDs, they were doped with 1, 2, 3% molar ratio of Ca2+ and 1, 2, 3, 4 % molar ratio of La3+. As a result, the QDs maintained the crystallite size and the sample doped with 1% of Ca2+ presented a high specific surface area (~412 m2.g-1), increased the interfacial component from 60 to 64%, and showed a decrease in bandgap from 3.02 to 2.72 eV, making it possible to carry out the degradation of tetracycline antibiotic using UV-vis.

C:P10  Multi-nozzle Spray Synthesis of Inorganic Nanoparticles: Early Stage of a New Process
G. GALLAND, M. Comet, D. Spitzer, NS3E - CNRS, Saint-Louis, France

The research project explores a new synthesis method for molecular powder materials called "Spray Flash Synthesis" (SFS) based on a breakthrough technique patented by the NS3E laboratory. This technique originates from the previously developed Spray Flash Evaporation (SFE) process to avoid well-known limitations and drawbacks of conventional chemical synthesis techniques such as incomplete reactions, low control of morphology and structure, non-uniformity and non-scalability. The SFS is a process that can directly elaborate sub-micron particles in a single step. The process consists of spraying the reagents dissolved in solutions via one or several nozzles into a vacuum chamber. Two heaters are integrated into the system: (1) an infrared system to enhance solvent evaporation and crystallization, (2) a calcination furnace to synthesize the inorganic nanoparticles. We will show practical examples of advanced materials such as BaTiO3 perovskite and YBCO superconductor. Subsequently, other inorganic and inorganic molecules will be synthesized to demonstrate the potential of SFS in tomorrow's syntheses.

C:P11  Plasma Firing of Ceramics
D.R. WING, D.R. Boughton, S. Kramel, J.H. Citriniti, L.A. Congdon, Corning Research and Development Corporation, Corning, USA

An investigation into the use of plasma-generated gases to fire ceramics was performed.
The goal was to demonstrate the completion of reactions up to 1000°C. The process time, RF power, sample distance from the plasma, and gas flow rate and gas mixture were
varied in the study. Weight loss, TGA and DSC analysis was performed on the plasma fired samples to determine the extent of the completion of reactions.

C:P12  Simulation of Heat Transfer on In-Situ Derived Alumina-TiB2 Composites
E. Daskalakis, A. Jha, A. Scott, A. Hassanpour, School of Chemical and Process Engineering, University of Leeds, Leeds, UK

The presentation focuses on the simulation of the heat transfer taking place in an in-situ derived ceramic composite based on alumina/ titanium diboride ceramics, in which the precursor materials are aluminium mixed with TiO2 and B2O3. The ignition of Al-TiO2-B2O3 mixture, triggers a highly exothermic self-sustaining aluminothermic reaction (Al+TiO2+B2O3, DH= 2,736 J/kg) in the absence of atmospheric oxygen. Consequently, a ceramic phase mixture consisting of alumina and TiB2 forms spontaneously, showing a range of morphologies of phases. A reaction mechanism for the completion of self-sustaining reaction is proposed for ball milled and unmilled mixtures, consisting of aluminium metal particles coated with shattered nano particles of TiO2 and B2O3. Thermal analysis of the Al-TiO2-B2O3 powder mixture, X-ray diffraction, and scanning electron microscopy of products demonstrate the mechanism of self-sustaining reaction and phase transformation. Using the Abaqus software, the simulation of the heating and heat dissipation during reaction in single-coated Al particle and in compacted Al-TiO2-B2O3 powder mixture was carried out to supplement the experimental data.

C:P13  Kinetic Studies of High Entropy FeNiAlCo and FeNiAlCoCr Alloys Formation at High Heating Rates
Kh. Nazaretyan, M. Tumanyan, A.B. Nalbandyan Institute of Chemical Physics, Yerevan, Armenia; D. Moskovskikh, A. Nepapushev, National University of Science and Technology MISIS; S. Aydinyan, A.B. Nalbandyan Institute of Chemical Physics, Yerevan, Armenia and Tallinn University of Technology, Tallinn, Estonia; S. Kharatyan, A.B. Nalbandyan Institute of Chemical Physics, Yerevan, Armenia

For the time being insufficient attention has been paid to survey the salient features of phase and structure formation patterns in high-entropy alloys (HEAs). The mechanism of metals’ interaction aimed at the preparation of FeNiAlCo and FeNiAlCoCr HEAs via high-speed temperature scanner technique was studied. Kinetic parameters of the interaction in the metals mixtures were determined for the non-activated and mechanically activated mixtures at heating rates from 100 to 2600 K/min. The effect of introducing chromium as the fifth ingredient into the FeNiAlCo system was revealed: in the Fe-Ni-Al-Co-Cr system the characteristic temperatures corresponding to exothermic effects on the heating curves were found to decrease and the activation energy value – increases, as compared to the Fe-Ni-Al-Co system. The effective Ea values for both non activated and activated Fe-Ni-Al-Co and Fe-Ni-Al-Co-Cr mixtures were determined. The increase in duration of mechanical activation from 0 to 5 min, leads to substantial decrease in the initiation temperature of exothermic interaction from 1023 K to 723 K in the both systems. As a result of interaction at high heating rates the formation of single phase FeNiAlCo and FeNiAlCoCr HEAs were observed.

C:P14  Formation of Ti2AlNx Max-phase by “Hydride Cycle” and SHS Methods
A.G. Aleksanyan, S.K. Dolukhanyan, D.G. Mayilyan, G.N. Muradyan, O.P. Ter-Galstyan, N.L. Mnatsakanyan, A.B. Nalbandyan Institute of Chemical Physics of NAS of Armenia, Yerevan, Armenia

In the present work the result of investigations of Ti2AlNx Max-phase synthesis are presented, by using “hydride cycle” (HC) and self-propagating high-temperature synthesis (SHS) methods. The algorithm for Ti2Al obtaining can be presented by the following scheme: synthesis of nitrogen solid solution in Ti and synthesis of titanium hydridonitride by SHS method, preparation of 2TiNxHy+Al mixture, cold isostatic pressing of the sample in form of cylindric tablet and further dehydrogenation-sintering, i.e. synthesis of Ti2AlNx Max-phase by HC method. The peculiarities of structure and materials formation regularities were investigated by staged study of physical-chemical properties of intermediate materials. Phase composition, crystal lattice parameters of initial reagents (TiNx, TiNxHy) were determined by XRD. Hydrogen and nitrogen content were determined by chemical analysis method. After HC the sample were identified as single-phase Ti2AlNx Max-phase. Comparing DTA and XRD data for separate initial reagents and the mixture, it was shown, that the presence of hydrogen in the reaction space has it’s influence on the mechanism of Ti2Al Max-phase formation. Solid phase character of interaction between TiNxHy and Al were established.

C:P15 Self-propagating High-temperature Synthesis of MAX-phases in Ti-Zr-Al-C System
N.N. AGHAJANYAN, S.K. DolUKhANyAN, o.P. TeR-GAlSTyAN, G.N. mURADyAN, K.V. ASATRyAN, A.B. Nalbandyan Institute of chemical Physics of Armenian National Academy of Sciences (IchPhNAS RA), yerevan, Armenia

This work presents the results of studying the formation in Self-propagating High-temperature Synthesis (SHS) mode of quaternary MAX-phases with stoichiometry (Tix Zr1-x)2AlC (x = 0-1) based on Ti-Zr-Al-C. The combinations of Ti, Zr, Al, and lamp black at various Ti/Zr/Al/ Cratios were thoroughly mixed, pressed into cylindrical tablets, and placed in the SHS reactor. Then, the combustion was carried out in the environment of argon or hydrogen at pressures not exceeding 3 atm. The temperature of combustion reached 1460–1495°C in hydrogen, and 1569–1600°C in argon. The influence of process parameters on the microstructure and crystallographic parameters of formed phases was elucidated. MAX-phases formed in a result of combustion of (TixZr1-x)2+Al+C mixture. According to X-ray phase analysis, most portion of MAX-phase (74.3 mass. %), accompanied with FCC solid solution of (Ti,Zr)Cy carbides (25.7 wt. %), formed at combustion of (Ti0.9Zr0.1)2AlC mixture in argon. The crystal lattice parameters of this MAX-phase structure: a = 3.066 Å; c = 13.7432 Å, c/a ratio = 4.48,were characteristic of "211", the parameter of FCC carbide solid solution (a=4.3249Å).

C:P16  Synthesis of Nanoscale Antiperovskite Complex Nitrides for Catalytic and Magnetic Applications
N.H. Amirkhanyan, M.K. Zakaryan, A.B. Harutyunyan, A.B. Nalbandyan Institute of Chemical Physics, Yerevan, Armenia

The counterparts of perovskites, known as antiperovskites, are electronically inverted derivatives of perovskites, exhibiting a number of physical properties not typical for those compounds. Nanoscale antiperovskite materials are a rising star family of functional materials with potential applications in energy conversion and storage devices, nano-electronics, and advanced thermal management technologies. Taking into account the problems of obtaining nanoscale antiperovskites, in this study a new approach for the synthesis of antiperovskites with a homogeneous structure was developed. To synthesize antiperovskite complex nitrides, such as Ni3CuN and Ni3FeN, that attract significant attention due to interesting catalytic and magnetic properties, the solution combustion synthesis (SCS) approach was applied. The combustion process was realized in aqueous solutions of the Ni(NO3)2 - Cu(NO3)2 - C6H12N4 and Ni(NO3)2 - Fe(NO3)3 - C6H12N4 systems. The products were examined by the scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses.

C:P17  Pressure-less Glass-ceramic Joining of SiC/SiC Nuclear Fuel Clads for Light Water Reactors
S. DE LA PIERRE1, M. Herrmann2, M. Ferraris1, 1Department of Applied Science and Technology (DISAT), Politecnico di Torino, Italy; 2Institute of Power engineering, Technische Universität Dresden, Germany

Several materials have been proposed for joining of SiC/SiC components for nuclear light water reactors.
Among them, some Silica-Alumina-Yttria (SAY) glass-ceramics gave promising results as pressure-less joining materials for slurry-based joining technologies suitable for a nuclear environment.
The present work reports on a Silica-Alumina-Yttria (SAY) glass-ceramic pressure-less joining options for SiC-based components; the same SAY glass-ceramic can be been used to join SiC/SiC composites by traditional furnace heating and by localized heating, then coated by Cr layer to protect the joining area from hydrothermal corrosion.
Morphology, micro-structure, mechanical test and autoclave test in pressurized water reactor (PWR) conditions, on SiC/SiC tubes joined to SiC/SiC end-plugs, will be discussed.
Acknowledgement: Part of the research leading to these results has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 740415 Project “IL TROVATORE - Innovative Cladding Materials for Advanced Accident-Tolerant Energy Systems”.

C:P18  Influence of the Sintering Parameters on Microstructure Development and Mechanical Properties of (Mo-Nb-Ta-V-W)C based High-entropy Carbides
R. SEDLAK, A. Kovalčíková, T. Csanádi, J. Dusza, Institute of Materials Research, Slovak Academy of Sciences, Division of Ceramic and Non-Metallic Systems, Košice, Slovak Republic; H. Ünsal, P. Tatarko, M. Tatarková, P. Šajgalík, Institute of Inorganic Chemistry, Slovak Academy of Sciences, Bratislava, Slovak Republic

A detailed systematic study investigates the influence of the sintering parameters on microstructure development and basic mechanical properties of (Mo-Nb-Ta-V-W)C high-entropy carbides. Extensive series of single-phase high-entropy ceramic materials with high relative densities were prepared by ball milling and a two-step field assisted sintering technology (FAST). Sintering conditions of 14 prepared HEC samples were modified. The sintering temperature varied from 1450 to 2200 °C, dwell time was at an interval of 5 to 20 min. Microstructural characterization was performed by scanning electron and transmission electron microscopy. Basic mechanical properties, such as hardness, fracture toughness and elastic modulus were measured. The relationship between microstructural development and basic mechanical properties has an important role in the further development of these perspective materials. A near fully dense, single-phase (Mo0.2Nb0.2Ta0.2V0.2W0.2)C material with the required mechanical properties was successfully obtained at a significantly lower sintering temperature of 1600 °C, dwell time of 20 min, and applied pressure of 70 MPa in the present work in comparison with previous studies.
Acknowledgement: Supported by APVV project SK-UA-21-0074, APVV 19-0497, and VEGA 2/0175/21

C:P19  Improvement of the Mechanical Properties of TiB2 for Armour Applications using Different Additives and Sintering Techniques
S. TARABORELLI, S. Failla, D. Sciti, CNR Faenza, Italy

TiB2 is a promising material in several fields including impact resistant armour, seals, cutting tools, crucibles and wear resistant coatings given its physical, mechanical and chemical properties, in particular thanks to the combination of high hardness and exceptional wear resistance. It is however very difficult to sinter below 2000°C, also under mechanical pressure, and is limited by its low fracture toughness. By using sintering additives, it is possible to improve the sintering process and increase the mechanical properties since the additives react with oxidized layers to form secondary phases.
In this study, we explored different preparation methods, various combinations of additives (B4C, Si3N4 and MoSi2), and sintering techniques (hot pressing and pressureless sintering). Thanks to the synergy between optimized process and tailored composition, an almost fully dense material was obtained at 1700°C with hardness of 24.4 ± 0.2 GPa and fracture toughness of 5.4 ± 0.2 MPa m0.5. However, the highest hardness value (30 ± 1 GPa) was obtained for samples sintered by pressureless sintering, featuring a core-shell grain structure.

C:P20  Nanoindentation of Dual-phase High-entropy Ultrahigh Temperature Ceramics
A. NAUGHTON DUSZOVA1, L. Timková1, T. Csanádi1, M. Vojtko1, P. Tatarko2, V. Kombamuthu3, H. Ünsal2, M. Tatarková2, P. Hvizdoš1, 1The Institute of Materials Research, Slovak Academy of Sciences, Košice, Slovakia; 2Institute of Inorganic Chemistry, Slovak Academy of Sciences, Bratislava, Slovakia; 3CEMEA - Center of Excellence for Advanced Materials Applications, Slovak Academy of Sciences, Bratislava, Slovakia

The experimental materials, fine-grained dual-phase, high-entropy ceramics (DPHE-HECs) (Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)B2-(Ti0.2Zr0.2Hf0.2Nb0.2Ta0.2)C were prepared from powders synthesized via a boro/carbothermal reduction. They were processed by Spark Plasma Sintering (SPS) in argon from temperatures from 1900°C to 2200°C under 70 MPa. According to the results the optimized sintering condition is sintering at 2000°C. and this system is the subject of recent investigation. The microstructure characteristics were studied using scanning electron microscopy, (ZEISS AURIGA) and EDX analyses. Nanoindentation was carried out using a Berkovich diamond tip applying continuous stiffness measuring (CSM) mode with a maximum depth of 150 nm. Indents were prepared, arranged in 10×10 arrays with a distance between the indents of 6 μm. The nanohardness of the HEB and HEC are with mean values of 43 GPa and 37.4 GPa, respectively. The Young modulus for HEB is significantly higher with a mean value of 766 GPa in comparison to the Young modulus of HEC with mean value of 536,5 GPa.

C:P21  Towards Increasing the Yield and Enhancing the Quality of In-plane Vacancy Ordered MXenes (Mo1.33CTz and W1.33CTz¬) Obtained from their In-plane Ordered i-MAX Phases (Mo2/3Y1/3)2AlC and (W2/3Y1/3)2AlC
J. HALIM, J. Rosen, Material Design Division, Department of Physics, Chemistry and Biology (IFM), Linköping, Linköping University, Linköping, Sweden

Introducing point defects in two-dimensional (2D) materials can alter or enhance their properties. Recently, it was shown that ordered vacancies can be introduced in MXenes by selective etching of Al and Sc atoms from the chemically ordered parent 3D i-MAX phases (Mo2/3Sc1/3)2AlC and (W2/3Sc1/3)2AlC. Both MXenes displayed interesting properties. For example, Mo1.33CTz showed an enhancement in the volumetric capacitance of 65% compared to its counterpart Mo2C with no vacancies, while W1.33CTz showed promising performance as a catalyst for the hydrogen evolution reaction. However, both MXenes were obtained from Sc-containing i-MAX phases, which are somewhat expensive. Attempts have been made to synthesize both MXenes from i-MAX phases containing the less expensive and more abundant element Y, though with a resulting lower yield and reduced quality as compared to the corresponding material obtained from the Sc-based parent material. Herein, we demonstrate methods to improve the quality of both (Mo2/3Y1/3)2AlC and (W2/3Y1/3)2AlC i-MAX phase through powder synthesis. Furthermore, we show evidence for resulting high-quality MXene Mo1.33CTz and W1.33CTz, of a highly improved yield, and synthesis of free-standing flexible films for further property analysis.

C:P22  Sol-gel Assisted Synthesis of New Carbonitride MAX Phases V2GaC1-xNx and Cr2GaC1-xNx
N. KUBITZA, Technische Universität Darmstadt, Darmstadt, Germany; C.S. Birkel, Arizona State University, Tempe, AZ, USA

MAX phases are ternary layered compounds that belong to the class of transition metal carbides and nitrides. Over the recent years, the number of known MAX phases has increased to more than 150 systems. However, only two of them can be attributed to carbonitride phases. By combining the so-called „urea-glass method“ with conventional preparation techniques in a two-step process, we have synthesized V2GaC1-xCx and Cr2GaC1-xNx as new members in the field of carbonitride MAX phases. First, nanoparticular ternary precursors (VC1-xNx, CrC1 xNx) are prepared, which are then thoroughly mixed with elemental precursors to reach MAX phase stoichiometry. The product formation is finalized by heat treatment using a conventional furnace and microwave heating, respectively. X-ray powder diffraction data, Electron energy loss spectroscopy, and X-ray photoelectron microscopy prove the carbonitride character of the materials. The morphology was elucidated by electron micrographs. Here, in addition to typical anisotropic layered MAX phase structures, finer substructures such as needle- and drop-like particles partially covering the surface, can be observed. Furthermore, magnetometry, as well as transport property measurements reveal a superconducting state for the Cr2GaC1-xNx phase below 6.1 K.

C:P23  Inherently Nanolaminated Mn5Ge3C0.5 Epitaxial Films: A New Superstructure Inferred from the 55Mn NMR Study
E. JEDRIKA1, M. Wójcik1, R. Kalvig1, M. Petit2, L.Michez2, 1Institute of Physics, Polish Academy of Sciences, Warsaw, Poland; 2Aix Marseille Univ, CNRS, CINAM, Marseille, France

Mn5Ge3(001)/Ge(111) epitaxial films attracted a lot of interest as a potential source of polarized carriers directly into Ge. Mn5Ge3 is a metallic ferromagnet crystallizing in the hexagonal D88 structure where the Mn atoms occupy 4(d) and 6(g) sites. The 2(b) lattice voids inside the Mn[6(g)] octahedra were shown to host a carbon and the chain of such octahedra along the c-axis represents a characteristic chimney. The interest of carbon-doping consists in enhancing the Curie temperature up to 430 K. With the aim to understand the effect of carbon, a comprehensive 55Mn NMR study has been performed on the series of Mn5Ge3Cx films (30nm) with a nominal carbon concentration 0
[1] R. Kalvig at al. Phys. Rev. B 105, 094405 (2022)

C:P24  Transport and Mechanical Properties of Copper-MAX-phases Composites Obtained by Spark Plasma Sintering
J.-P. ERAUW, V. Dupont, C. Gajdowski, Belgian Ceramic Research Centre (BCRC), Mons, Belgium

MAX phases reinforced copper matrix composites have been recently investigated as potential electro-friction materials owing to the capability of the former to strengthen the Cu without impacting too much the transport properties thereof. In the present study, both Ti2AlC and Ti3SiC2 based copper matrix composites have been elaborated by spark plasma sintering at 850°C and characterized. Pure copper, Ti2AlC and Ti3SiC2 dense compacts have been synthesized as well by SPS as reference materials. Results show that moderate filler contents, in the range 5 - 10 vol%, are sufficient to substantially influence the transport and mechanical properties of the copper matrix. Depending on the filler type, content and mean particle size, the electrical and thermal conductivities at room temperature range respectively from 10.000 to 350.000 s/cm and from 50 to 250 W/m.K. Concurrently, the hardness, stiffness and wear resistance are significantly improved. This improvement, although also dependent on the nature of the MAX phase, is primarily dictated by the filler content. Finally, the microstructural investigation of the composites indicates that the MAX phase particles are homogeneously distributed in the copper matrix and that limited reaction took place between the matrix and reinforcement.

C:P25  Low-temperature Plasma Treatment in Designing the Morphology of Titania Nanofibers
I. SHEPA, E. Mudra, M. Vojtko, O. Milkovic, J. Dusza, Institute of Materials Research, Slovak Academy of Sciences, Košice, Slovak Republic; D. Pavlinak, Department of Physical Electronics, Masaryk University, Brno, Czechi Republic; P. Tatarko, Institute of Inorganic Chemistry, Slovak Academy of Sciences, Bratislava, Slovak Republic; V. Antal, J. Bednarcik, Institute of Experimental Physics, Slovak Academy of Sciences, Košice, Slovak Republic

This work describes the low-temperature plasma treatment of the electrospun composite TiO2/PVP preceramic microfibers. The fibrous mats were treated by Diffuse Coplanar Surface Barrier Discharge (DCSBD) in three different atmospheres: oxidative – air, reductive – H2 and inert – N2. The distance between samples and the surface of the electrode plate was set 0.3 mm for the maximum effect, exposure times were 10, 30 and 60 min at the input power of 400 W. Impact of the plasma treatment in different atmospheres on the morphology and chemical composition of the composite microfiber mats were studied. This type of treatment led to the formation of flexible TiO2/PVP core/shell fibers. For evaluation of the polymer decomposition and ceramics formation – DSC/TG, Raman spectroscopy and FTIR analysis were used. For the characterization of the morphology and chemical composition of the fiber surfaces XPS and the scanning electron microscopy coupled with EDX analysis were applied. It was found that thin ceramic layer was formed on the surface of the fibers, thickness and morphology of which depends directly on the exposure time and atmosphere. The main aim of this work is to compare the impact of plasma treatment in the atmosphere with different chemical nature on the same composite system.

C:P26  Synthesis of Nanostructured Tungsten-doped Niobate-Perovskites via Ultrasonic Spray Pyrolysis
S. LANFREDI1, F.R. Praxedes2, J. Matos3, M.A.L. Nobre1, 1São Paulo State University (Unesp), School of Technology and Sciences, Presidente Prudente, SP, Brazil; 2São Paulo State; University (Unesp), Institute of Biosciences, Humanities and Exact Sciences, São José do Rio Preto, SP, Brazil; 3Instituto de Ciencias Químicas Aplicadas, Facultad de Ingeniería, Universidad Autónoma de Chile, Santiago, Chile

Alkali niobate of type perovskites have emerged as a potential photocatalysts of optical gap modulated by solid solution formation from of K0.5Na0.5Nb3O3. Doping of structure on the niobium site plays a significant role upon properties such as superconductivity, ferroelectricity, photovoltaic energy and photocatalysis. Furthermore, W-doped niobate-based semiconductors are relevant for the scaling-up of the solar-driven degradation of pollutants and solar energy conversion. In this work, new finds to design precursor solution were investigated modeling rules for the W-doped potassium-sodium niobate powders synthesized by the Ultrasonic Spray Pyrolysis method. In this way, this work is aimed to prepare hollow spheres composed of K0.5Na0.5NbO3 by Ultrasonic Spray Pyrolysis. This method exhibits a wide range of advantages stemming simplicity and effectiveness, as well as the production of different hollow particle morphologies. The crystalline structure was evaluated by the Rietveld refinement method and symmetry decomposition. Results indicated a phase mixture with two symmetries, as follow: monoclinic Pm (77 %) and orthorhombic Pbcm (23 %). The W6+ aliovalent in the host structure is discussed in terms of polarization, optical features and structural stabilizing.

C:P27  Silicon Carbide Thin Films Deposited by HiPIMS on Ti-6Al-4V Substrates to Improve the Adherence for Tribological Applications
A.C. Merij1, K.G.Grigorov2, G.F.C.Almeida3, A.A.Couto3, 4, A.A. Arbex3, A.S. da Silva Sobrinho5, D.M.G. Leite5, C.A.M.Oliveira3, M. Massi3, 1Federal University of São Paulo, ICT/UNIFESP, São José dos Campos / SP, Brazil; 2Space Research and Technology Institute, Acad. G. Bonchev, Bl.1, Sofia, Sofia, Bulgaria; 3Mackenzie Presbyterian University, School of Engineering-PPGEMN, São Paulo / SP, Brazil; 4Nuclear and Energy Research Institute, IPEN/USP, São Paulo / SP, Brazil; 5Technological Institute of Aeronautics, ITA/DCTA, São José dos Campos / SP, Brazil

Ti-6Al-4V alloys are applied mainly in aeronautical and space areas, but interface phenomena can turn its usability unsuitable for thermal cycling applications, due to pores, cracks, or inclusions formations caused by diffusion of the environment’s elements. Ceramic protection coatings can be used to solve these problems. In this work, silicon carbide (SiC) was deposited on the Ti-6Al-4V alloy by HiPIMS (High Power Impulse Magnetron Sputtering) at different target distances (90, 135 and 150 mm), a chromium interlayer was added to improve its adhesion, deposited by DC magnetron sputtering. Studies showed that HiPIMS allows a large ionization of the particles ejected from the target, resulting in uniform films with better adherence. Film characterizations was performed by FT-IR, SEM, Rockwell C indentation, and profilometry. Films grown at 90 mm had better adhesion. But the closer the sample is to the target, the chances of more energetic particles colliding with its surface are higher, increasing the film tensions and impacting its final hardness. Preliminary results show that these higher tensions are related to the increase of film’s hardness, indicating the possibility of tribological applications.

C:P28  Photonic Multilayer Structure for Near-infrared Blocking as Energy-saving Window
Jiwon Kim1, Sangwon Baek1, Jae Yong Park1, Kwang Ho Kim2, Jong-Lam Lee1, 1Department of Materials Science and Engineering, Pohang University of Science and Technology, Pohang, South Korea; 2Department of Materials Science and Engineering, Pusan National University, Pusan, South Korea

Blocking near-infrared (NIR) is indispensable for saving energy consumed to maintain an interior temperature in buildings. However, it is hard to achieve both high visible transmittance and high NIR reflectance for energy-saving windows. Here, we demonstrate a TiO2/Ag/TiO2/SiO2/TiO2 multilayer film on a glass substrate to block the entire NIR (800 ≤ λ ≤ 2500 nm) while maintaining high visible transmittance. We first design and optimize the thickness of a TiO2/Ag/TiO2 structure; the metal layer reflects NIR and the dielectric layers increase visible transmittance with zero reflection condition. To further enhance NIR-blocking efficiency, we implement a TiO2 back reflector with a SiO2 spacer to TiO2/Ag/TiO2 structure. TiO2 layer with high refractive index sandwiched between glass substrate and SiO2 with low refractive indices can induce additional Fresnel reflection without sacrificing transmittance in visible light. The optimal photonic multilayer film shows solar energy rejection 89.2% (reflection 86.5%, absorption 2.7%) in NIR, visible transmittance 69.9%. Furthermore, the blocking capability in NIR of the designed multilayer film is maintained over a wide range of incident angles of light.

C:P29  Insulator-conductor Transition of Plasma Sprayed Alumina (Al2O3) Coating upon Reinforcement of Carbonaceous Nanofillers
D.K. PANDEY, A.K. Keshri, Indian Institute of Technology Patna, Bihar, Patna, India

Splats are the paramount unit of any plasma sprayed coating and their successive deposition leads to coating formation. Present work studies the electrical conductivity variation of plasma sprayed alumina single splats on the reinforcement of carbonaceous nanofillers, namely carbon nanotube and/or graphene nanoplatelets using conductive atomic force microscopy (cAFM). Incorporation of CNTs and GNPs in the Al2O3 matrix resulted in spherical splats, instead of fragmented one (like Al2O3 splats). Current mapping for the Al2O3 splat during cAFM revealed a completely black region on the screen, signature of insulating behavior. The addition of CNTs and/or GNPs in the matrix dramatically enhanced the electrical conductivity of the Al2O3 splats, turning its non-conductive map to conductive one. The highest conductive map was obtained for the synergistically reinforced splats. This improvement was attributed to higher electrical conductivity of the reinforcement as well as formation of 3D conductive channel for electron transport in the matrix.

C:P30  Studies on Structure, Redox Properties and Catalytic Activity of Cu-doped Strontium Titanates obtained from Modified Pechini Method
A. MIZERA, E. DroZdZ, AGH University of Science and Technology, Kraków, Lesser Poland, Poland

Perovskites gained wide research interest due to the possibility of substituting the host elements with dopant (guest) elements without changing the structure (to some extent of the dopant content). Strontium titanate perovskite is mixed oxide crystallizing in a cubic crystal system. It is a dielectric material in its pure form, but doping it in the Ti position can alter its electronic structure leading to an increase of electric conductivity. In addition, it is also possible to dope SrTiO3 with elements which are catalytically active in specific reactions. In this work, we synthesized Cu doped strontium titanates using the modified Pechini method. The modification was based on the replacement of polyhydroxy alcohol (such as ethylene glycol) with polymer – poly(vinyl alcohol) (PVA). The obtained materials were tested for their phase composition (XRD) and the ability to undergo redox reactions by temperature-programmed reduction and oxidation (TPR/TPOx). Although such materials were previously synthesized, our goal was to check their catalytic activity in the selective catalytic reduction of NOx with ammonia (NH3-SCR).
AM has been partly supported by the EU Project POWR.03.02.00-00-I004/16

C:P31  The Influence of Humidity on Perovskite Niobate Dielectrics
M. Frey1, C.K. YANG1, T. Hanemann1,2, 1University of Freiburg, Department of Microsystems Engineering - Laboratory for Materials Processing, Freiburg, Germany; 2Karlsruhe Institute of Technology, Institute of Applied Materials, Karlsruhe, Germany

In a lot of electronic parts, ceramics have become indispensable. They act as structural, piezo active and as ferro- or dielectric materials. Due to its outstanding performance, PZT is still a commonly used ceramic even though it contains lead and causes, therefore, serious health and environmental issues. Titanates and Niobates are promising candidates to replace PZT, but their properties and processing behavior differs. In this work we examined sodium-Potassium niobates and wanted to address the dependence of the dielectric properties within changing humidity’s. The relative permittivity can be increased from about 500 to 3000 between a dried and a humidified sample. Via electrophoretic deposition we can produce thin ceramic polymer composite layers which potentially can be used as cheap and easy to produce humidity sensors. The polymer content can be fitted to the needs of the application and can be risen to 30 volume per cent.

C:P32  Nanomechanical Probing of Lead-free Ferroelectrics
K. ZIBERNA1, 2, A. Drnovšek3, H. Uršič1, 2, T. Rojac1, 2, A. Benčan1, 2, 1Electronic Ceramics Department, Jožef Stefan Institute, Ljubljana, Slovenia; 2Jožef Stefan International Postgraduate School, Ljubljana, Slovenia; 3Department of Thin Films and Surfaces, Jožef Stefan Institute, Ljubljana, Slovenia

The use of ferroelectric materials in applications depends not only on good electromechanical properties, but also on the mechanical reliability of the material. While characterization of mechanical properties at the macroscopic and microscopic length scales can be routinely performed, characterization at the nanoscale using various microscopy techniques is a non-trivial task due to experimental challenges. In this contribution, we present the results of nanomechanical investigation of BiFeO3 and (K, Na)NbO3 based ferroelectric materials using a nanoindentation system in the scanning electron microscope. The system allows us to study the dynamic structural changes, such as changes in domain structure, and measuring mechanical properties of domains/domain walls in the material during nanoindentation. The mechanical properties of domains/domain walls of different types are discussed and compared with results obtained by nanomechanical probing using atomic force microscopy.

C:P34  Understanding Electrolyte Influence on Lithium Plating via Potential-driven Deposition
E. WINTER1, T.J. SCHMIDT2, S. TRABESINGER1, 1Electrochemistry Laboratory, Paul Scherrer Institut, Switzerland; 2Energy and Environment Research Division, Paul Scherrer Institut, Switzerland / Laboratory of Physical Chemistry, ETH Zürich, Switzerland

In the age of renewable energy and electrified mobility, the demand for high-capacity lithium-ion batteries is higher than ever. This has been driving research for new battery designs; one of the hottest candidates of which is the lithium-metal battery (LMB). Metallic lithium as an anode, though already known for decades, has experienced a renaissance due to its potential to almost double energy density. However, a key requirement for LMBs is a compatible electrolyte that allows reversible—and, most importantly, safe—cycling. Screening electrolyte performance with lithium metal is therefore crucial for the development of a prospective solution. For this, inspired by hydrogen pumping experiments typically carried out in fuel cells, we deposited metallic lithium on copper in a potentiostatic plating process using a selection of common battery electrolytes. In the first part of our study, we elaborate on the relation between the shape of the potential-current curve and observed lithium deposition by post-mortem scanning electron microscopy. In addition to that, by correlating potentiostatic plating results to physical electrolyte properties, we discuss potential applications of the method for future screening of electrolytes.

C:P35  Efficient Synthesis of High-sulfur-content Cathodes for High-performance Li-S Batteries based on Solvothermal Polysulfide Chemistry
YU-TING WENG, Nae-Lih Wu, Advanced Research Center for Green Materials Science and Technology, National Taiwan University, Taipei, Taiwan

A novel solvothermal polysulfide (PS) chemistry enables a facile and highly efficient process for synthesizing sulfur-carbon (S–C) composite powders containing up to 90 wt.% S for high-performance Li-S batteries. Molecular dynamics calculations and experimental analyses reveal the formation of PSs upon dissolution of elemental S in N-methyl-2-pyrrolidone (NMP) at elevated temperatures and efficient infiltration of the PSs into the carbon host driven by the strong coupling with the C surfaces. The coupling enables extensive contact between S and C in the composite, leading to promising electrochemical properties for Li–S battery applications. In the power-type configuration, the composite cathodes having medium-to-high S contents (55 and 75%) demonstrate stable capacity at high current densities up to 100C (1C= 1670 mA g-1-S) and no capacity fade up to 1000 cycles at 2C. In the energy-type configuration, a high-S-content and high-loading (90%-S, 4.2 mAh cm-2) cathode shows a specific capacity of 1440 mAh g−1 (86% S utilization) and 90% capacity retention after 300 cycles. This synthesis method enables significant advancement in realizing large-scale applications of Li-S batteries.

C:P36  Ru/La0.75Sr0.25Cr0.5Mn0.5O3-d Catalysts for Syngas Synthesis in IT-SOFCs
J. ISOPI, S. Fasolin, S. Barison, CNR, Padova, Italy

The La0.75Sr0.25Cr0.5Mn0.5O3-δ (LSCM) catalyst and its composite with Ru (Ru/LSCM) were investigated as alternative anodes for the production of H2 and CO from H2O and CO2 in anode-supported intermediate temperature solid oxide fuel cells (IT-SOFCs). Ru/LSCM already have proven a strong selectivity for H2 and syngas production from propane and methane as well as good chemical stability in operation conditions. If the reduction of CO2 is proven viable, it opens the possibility of a role in carbon capture technology for this material. The LSCM powders were prepared by a sol–gel method based on a modified Pechini procedure. Single-phase LSCM perovskite powders were obtained. SEM imaging of the LSCM powders revealed particles in the 100–200 nm range with a homogeneous grain distribution. The deposition of 5 wt.% metallic ruthenium nanoparticles on the LSCM perovskite powders was carried out by a microwave-assisted procedure. In previous works, TEM investigations of Ru/LSCM composites showed a homogeneous distribution of metallic ruthenium nanoparticles with a mean grain size of around 2–3 nm. The catalytic activity of these potential anode materials was investigated using humidified CO2 as reagent and gas chromatography to analyze the products at room temperature, 300, 400 and 500 °C.

C:P37  Anti-counterfeiting Security Inks using Colour Tuneable Rare-earth doped Sol-gel Nano-glass-ceramics for Codification of Luminescent Patterns
C. Hernández-Álvarez, S. Torres-García, M. Medina-Alayón, P. Acosta-Mora, A.C. Yanes, J. del-Castillo, Universidad de La Laguna, La Laguna, Tenerife, Spain; A. Menéndez-Velázquez, Centro IDONIAL, Oviedo, Asturias, Spain; J. Méndez-Ramos, Universidad de La Laguna, La Laguna, Tenerife, Spain

Anti-counterfeiting strategies are competitively developed against fast-growing counterfeit markets as a corner stone for the next generation of luminescent security inks. In particular, rare-earth doped up-conversion luminescent materials present significant advantages compared to standard fluorescent dyes, such as invisibility in ambient light, excitation by low cost commercial NIR irradiation and a lack in background noise, due to negligible auto-fluorescence from the surface. However, more attention needs to be paid on the codification of overall emitted luminescence, so it will be more difficult to mimic by ever increasing sophisticated counterfeiters. Here we present up-conversion emissions in colour tuneable rare-earth doped sol-gel nano-glass-ceramics under NIR excitation at 980 nm. In particular, intensity ratios among UV and VIS up-conversion emission bands can be tailored by modifying doping concentration level. Specific doping level, excitation wavelength and focusing conditions give rise to a 3-level security level based on light-responsive encryption security patterns. A multi-digit-code based on these intensity ratios can be set from resulting spectra, providing a proof-of-concept test for light-responsive encryption security patterns.

C:P38  Influence of the Presence of Iron in the Form of Fe3O4 on the Manufacture of Lightweight Aggregates
T. COTES PALOMINO1, C.J. Cobo-Ceacero1, B. González-Corrochano1, A.B. López-García1, J.M. Moreno-Maroto1, A. Conde-Sánchez2, A.M. Martínez-Rodríguez2, M. Uceda-Rodríguez1, J. Alonso-Azcárate3, C. Martínez-García1, 1Department of Chemical, Environmental and Materials Engineering. Higher Polytechnic School of Linares, University of Jaén. Linares (Jaén), Spain; 2Department of Statistics and Operational Research. Campus Las Lagunillas. University of Jaén, Jaén, Spain; 3Department of Physical Chemistry. Faculty of Environmental Sciences and Biochemistry. University of Castilla-La Mancha, Avenida Carlos III, Toledo, Spain

This work is part of a research project whose objective is to determine the influence that ferrous-ferric oxide (Fe3O4) has on the possible expansion of artificial lightweight aggregates made from wastes with this iron phase in their composition, and to establish the relationship between the proportion of Fe3O4 and the values of the main technological properties of the materials obtained. Artificial aggregates were manufactured with proportions of kaolin, Fe3O4, cork powder and sodium carbonate ranging from 40%-100%, 0%-50%, 0%-5% and 0%-5%, respectively. The aggregates were sintered in a laboratory rotary kiln for 10 minutes. Sintering temperatures ranged from 1133°C to 1345°C, depending on the compositions of the mixtures.Using the design of experiments methodology, 34 different types of artificial aggregates were produced and different technological properties were determined. Bloating index values: -15.47% to 33.26%; loose bulk density values: 0.30 g/cm3 to 1.61 g/cm3; dry particle density values: 0.58 g/cm3 to 2.87 g/cm3; water absorption values: 0.31% to 21.44%; the crushing strength values, from 0.29 MPa to 19.39 MPa. It could be determined how the values of these properties are statistically related to the composition of the formulated mix.

C:P40  Alkali-activation of Fly-ash with Microwaves
B. HORVAT, M. Pavlin, V. Ducman, ZAG, Ljubljana, Slovenia

Alkali-activated materials represent a future alternative to nowadays conventional high-carbon-footprint building products like cement, concrete, ceramics etc. They are produced at low temperatures (below 100 °C) and from waste materials just in a few hours and up to a few days. To even further accelerate the alkali-activation synthesis of waste materials and increase the mechanical strengths, microwave irradiation of frequency 2.45 GHz, of powers up to 700 W and up to 25 s were used in the early stages of alkali-activation of fly-ash prepared in 2 either potentially most optimal mixture according to the final desired chemistry of the aluminosilicate network. Mechanical strengths of alkali-activated fly-ash show unique dependence on the dose of microwave irradiation. The influence of dose of irradiation differs for both mixtures noticeably, although just a slight variation was made in alkali (the difference is the addition of only 6 m% of NaOH calculated to the mass of precursor, which decreased the mass percent of water for less than 1 m%). However, the behaviour of compressive strength was similar for low amounts of irradiation dose. Based on the results obtained so far it seems that this innovative processing using microwave irradiation is highly perspective.

C:P41  Reuse of Waste Glass Wool generated in the Process of Demolition and Restoration of Buildings for the Production of Artificial Lightweight Aggregates
J.M Moreno-Maroto, A.B López García, S. León-Gutierrez, M.T. Cotes-Palomino, C. Cobo-Ceacero, M. Uceda-Rodríguez, C. Martínez-García, Department of Chemical, Environmental and Materials Engineering, Higher Polytechnic School of Linares, University of Jaén, Linares (Jaén), Spain

Abstract Waste recycling is one of the key elements to mitigate the environmental problems that threaten our society. Mineral wool is currently the most widely used insulation material in the European Union, so the amount of waste generated in the demolition and restoration of buildings has increased alarmingly. This work investigates for the first time the use of glass wool (GL) and rock wool (RW) as a component in the manufacture of lightweight aggregates, showing that both can be suitable raw materials considering the low density and high mechanical strength obtained. In addition, the use of LV would help to reduce the firing temperature significantly (700°C) compared to that normally used in the manufacture of these materials (approx. 1200°C), which would imply significant energy savings. In short, the tests carried out for the characterisation of lightweight aggregates suggest that mineral wool is associated with a cleaner production of these materials, as well as implying a reduction of this waste in landfills.

C:P42  LCA of W2L Pilot Façade Panels from Alkali-activated Stone Wool
A. LESEK1, M. Pavlin1, B. Horvat1, K. Malovrh Rebec1, F. Knez1, V. Ducman1, B. Matko2, M. Žajdela2, E. Sever2, A. Pavlin2, A. Kaiser3, 1Slovenian National Building and Civil Engineering Institute, Ljubljana, Slovenia; 2TERMIT, Moravče, Slovenia; 3Saint-Gobain Finland Oy, Helsinki, Finland

Wool2Loop project aims to solve one of the biggest challenges in the utilization of construction and demolition waste by upcycling stone wool waste into alkali-activated products (“geopolymer”) that can be reused back in the building and civil engineering industry. Our focus was to make façade panels from waste stone wool with compressive strength above 30 MPa, bending strength above 10 MPa, frost resistant and with the lowest possible environmental burdens, calculated by the means of LCA. LCA, made for the whole life cycle of the assessed panel shows that the production of the panels brings the majority of the environmental burdens compared to the rest of the life cycle. In the production stage, the water glass is the material that brings the biggest environmental burdens (on average 44% in different parameters), followed by the electricity consumed while producing the panel (average of 30%). Our secondary input – waste stone wool, which has the second-biggest mass on the other hand brings much less (on average 4% in different parameters). This assessment shows, that the use of secondary material, in this case, is viable from the environmental, as well as mechanical point of view.

C:P43  Use of Biomass Fly Ash as Filler in a Commercial Screed Mortar Formulation
M.N. Capela1, I.S. Vilarinho1, I.R. Vieira1, L.A. Tarelho2, P. SEABRA1, J.A. Labrincha1, 1CICECO - Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, Aveiro, Portugal; 2CESAM - Centre for Environmental and Marine Studies, Department of Environment and Planning, University of Aveiro, Aveiro, Portugal

The production of bioenergy from the fluidized bed combustion of biomass has increased worldwide. This process generates biomass fly ash (BFA), an inorganic solid waste that is commonly disposed of in landfills. Therefore, more sustainable management practices are being investigated such as its use in construction materials. In this work, the valorization of BFA, as a filler (5, 7.5, and 10 wt.%), in a commercial screed mortar formulation was evaluated. Before its use, BFA was grounded (Ø < 63 µm) and characterized (XRF, XRD, SEM, and particle size distribution). The effect of the incorporation amount on the bulk density, water absorption (by capillary and immersion), and flexural and compressive strength properties of the screed mortar was assessed. The obtained results show that it is possible to integrate up to 10 wt.% of grounded BFA in the commercial screed mortar formulation, preserving the required properties. In addition to the environmental advantages, this solution also has economic benefits through the elimination of the costs inherent to the BFA landfill and the reduction of expenses related with the acquisition of virgin raw materials.

C:P44  Incorporation of Bioleached Sulfidic Mine Tailings in One-part Alkali-activated Blast Furnace Slag Mortar
HE NIU, P. Kinnunen, M. Illikainen, Fibre and Particle Engineering Research Unit, University of Oulu, Oulu, Finland; I.J. Corfe, J. Kuva, A.R. Butcher, Geological Survey of Finland

Sulfidic mine tailings (SMTs) are potential waste materials from mining and mineral processing, and they can contain a high content of sulfur and metal(loid)s, even after bioleaching. Due to the large amount of tailings waste from historical mining, it is crucial to find alternative methods for utilizing such waste rather than permanent storage in tailings impoundments. One-part alkali-activated slag mortars are promising co-binder systems for the recycling of sulfidic mine tailings thanks to their practicability, easy transportation, and user-friendly production. In this work, up to 50 wt% mine tailings were incorporated into alkali-activated blast furnace slag (BFS) mortars. C-(N)-A-S-H gels were formed in all final samples with hydrotalcite zeolites. Tailings hardly participate in alkali activation, but they do have a considerable influence on physical and chemical properties. The 20 wt% tailings-containing sample showed the highest compressive strength of 91.1 MPa after 90 days of curing. In addition, the results of X-ray microcomputed tomography showed higher porosity when the mortar contains more tailings; thus, the sample with 10 wt% mine tailings showed the lowest porosity.

C:P45  Lightweight Mortars Prepared from Synthetic Glass Aggregates Formulated from Waste
M. ROMERO, I. Padilla, J.L. García Calvo, P. Carballosa, F. Pedrosa, A. López-Delgado, Eduardo Torroja Institute of Construction Science, IETcc-CSIC, Madrid, Spain

The aggregates industry worldwide is among the largest non-energy extractive activities. In Europe, about 86% of aggregates consumption comes from natural resources and only 14% is from synthetic or recovered aggregates. Man-made lightweight aggregates are in considerable demand in the construction sector for their use in the manufacture of mortars or concretes. This study was conducted to assess the applicability of glass aggregates produced from all-waste mixtures (glass cullet and waste carbonates) for the preparation of lightweight mortars. The influence of several processing variables (amount and character of foaming agents, firing temperature and time, among others) on the physical and mechanical features of the new lightweight artificial aggregates was evaluated. In addition, the aggregates were tested for their application in mortars. A comparison of the fresh state and mechanical properties of the mortars produced with the synthetic lightweight glass aggregates with those of a reference mortar produced with a commercial aggregate (arlite-based) was carried out. The results were satisfactory, but somewhat affected by the density of the aggregate.

C:P46  Valorization of Almond and Hazelnut Shell Residues as a Potential Resource in the Manufacture of Ceramic Bricks
A.B. López-García, T. Cotes-Palomino, J.L. García Rodríguez, C. Lerma Villar, M. Márquez Fernández, A. Rentero López, C. Martínez-García, Department of Chemical, Environmental and Materials Engineering, Scientific-Technological Campus of Linares, University of Jaén, Linares (Jaén), Spain

The recovery process converts materials that would otherwise be considered waste into new products, reducing the consumption of raw materials, the amount of waste generated, greenhouse gas emissions and to create new jobs. Current legislation and the Zero Waste strategy require finding suitable technologies for waste treatment and reduction. This fact, together with the fact that the construction industry is one of the key sectors of our economy, which mobilizes more natural resources, especially non-renewable ones, makes the production of sustainable bricks from industrial waste, which complies with the technical specifications required by the regulations, a very interesting initiative. The objective of this work is to study the technological feasibility of using almond and hazelnut shells, with different particle sizes (0.5, 0.71 and 2 mm), and mixed at 5%, with blond clay in different sizes (1 and 2 mm), using compression as a forming technique. The bricks were fired in a kiln at 1050 ºC for 1 hour. It was observed that, in general, the ceramic pieces with almond and hazelnut shells have lower bulk density, higher porosity, lower weight, higher water absorption and lower compressive strength values; it was also concluded that the particle size is not a determining factor.

C:P47  Characterization of YBa2Cu3O7 Films Grown on SrTiO3 and YSZ Substrates by Chemical Solution Deposition of Trifluoroacetates
A. BUSTAMANTE, A.M. Osorio, J. Flores, H. Sánchez, L. Sánchez, Universidad Nacional Mayor de San Marcos, Lima, Perú; L. De Los Santos, D.A. Ritchie, C.H.W. Barnes, University of Cambridge, Cambridge, UK

We report the characterization of YBa2Cu3O7 (YBCO) films grown on SrTiO3 and YSZ substrates by the trifluoroacetates chemical solution deposition method and following sintering with oxygen atmosphere at 860°C. The X-ray diffraction reveals (00ℓ) – oriented crystallites indicating epitaxial growth of the film in the c-direction. Despite granular morphology and the presence of Y2BaCuO5 and CuO as minor secondary phases, the technique shows the successful formation of the superconducting YBCO and preventing the formation of the unwanted BaCO3 phase. Rocking curve measurements of the (005) reflection for the YBCO/SrTiO3 was fitted with one Gaussian function with full width at the half maximum (FWHM) of 0.44° confirming that it consists of YBCO crystallites with different texture. For the sample grown on YSZ, Rocking curve was fitted with two Gaussian functions, one corresponding to the YBCO layer (FWHM 0.4°) and another to the substrate (FWHM 0.3°). The magnetic measurements taken in zero field cooling and field cooling modes confirm the formation of the superconducting YBCO with TC=91.8 and 85.7 K for the samples grown onto YSZ and SrTiO3, respectively.

C:P48  Systematic High-throughput Screening for Magnetic MAX phases
A.M. MALIK, J. ROHRER, K. ALBER, Technical University of Darmstadt, Darmstadt, Germany 

Layered nanolaminates that belong to a large family of ternary transition metal carbides and nitrides, are known as MAX (Mn+1AXn) phases. These phases if magnetic, owing to layered structure, can be promising candidates for spintronics and magnetocaloric applications. Up to date, very few magnetic MAX phases that are based on Mn and/or Cr, have been synthesized. In this work, we have systematically screened Mn+1AXn phases with ‘M’=Sc to Hg, ‘A’ from Group III-IVA, X=C or N and n=1,2,3 summing up to 1200 compositions. The stability is determined by the formation enthalpy relative to known competing phases that are present in the M-A-X chemical system, obtained from online database e.g. Materials Project. Based on calculated formation enthalpy, we predict ~170 new phases that so far have not been synthesised. However, only 6 in total, based on Cr or Mn, were found to have long-range magnetic order. The main conclusion of this study is that further work to obtain magnetic MAX phases should be focused on non-conventional single-M MAX phases and beyond.

C:P49  High-temperature properties of selected ZrB2-based carbide ceramic composites
A. KOVALČÍKOVÁ1,  M. IVOR1, 2, I. SHEPA1 , O. PETRUŠ1 , R. SEDLÁK1, D. MEDVEĎ1, 2, A. NAUGHTON DUSZOVÁ1, J. DUSZA1, 1Institute of Materials Research, Slovak Academy of Sciences, Košice, Slovak Republic;
2Faculty of Materials, Metallurgy and Recycling, Technical university of Košice, Košice, Slovak Republic


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