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MAX phases exhibit excellent combination of ceramic and metallic-like properties. In this work, MAX phase Ti3SiC2 powder was synthesized starting-off with different combinations of elemental powders and carbides. The powders used were Ti, Si, C, SiC and TiC in different combinations, molar ratios and powder size. Powders were heat treated on a vacuum furnace for different times and temperatures for in situ production of the Ti3SiC2 MAX phase. High purity synthesized samples were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM) in order to identify and quantify the different phase constituents present. The main phase constituents in the powders produced were Ti3SiC2 and TiSi2. Up to 94% of Ti3SiC2 MAX phase was obtained using Ti:SiC:C as starting powders in a molar ratio of 3:1.5:0.5. Different phase constitution was observed on the surface and the centre of the samples. An optimal starting powder composition, molar ratio, heat treatment temperature and time is proposed for the formation of high purity Ti3SiC2 MAX phase. Selected mixture was studied thermodynamically and a reaction mechanism of formation of the MAX phase is proposed. ; Las fases MAX presentan una excelente combinación de propiedades cerámicas y metálicas. En este trabajo se sintetizaron polvos de fase MAX Ti3SiC2 a partir de diferentes combinaciones de polvos elementales y carburos. Los polvos utilizados fueron Ti, Si, C, SiC y TiC en diferentes combinaciones, proporciones molares y tamaño de partícula. Los polvos se sinterizaron en un horno de vacío a diferentes tiempos y temperaturas para la producción in situ de la fase MAX Ti3SiC2. Las muestras sintetizadas de alta pureza se analizaron mediante difracción de rayos X (XRD) y microscopía electrónica de barrido (SEM) para identificar y cuantificar las diferentes fases constituyentes presentes. Las principales fases constituyentes en los polvos producidos fueron de Ti3SiC2 y TiSi2. Se obtuvo hasta un 94% de fase MAX Ti3SiC2 utilizando como polvos de partida Ti:SiC:C en una proporción molar de 3:1,5:0,5. Se observó diferente formación de fase en la superficie y en el centro de las muestras. Finalmente, se propone una composición óptima de polvo de partida, relación molar, temperatura de sinterización y tiempo para la formación de la fase MAX de Ti3SiC2 de alta pureza. La mezcla seleccionada se estudió termodinámicamente y se propone un mecanismo de reacción para la formación de la fase MAX. ; The authors would like to thank the funding provided for this research by the Regional Government of Madrid (Dir. Gral. Universidades e Investigación) through the project P2018/NMT4411 (ADITIMAT-CM), the Spanish Government through the Ramón y Cajal contract RYC-2014-15014 and the project MAT2012-38650-C02-01.

The goal of this work was to combine the physical barrier properties provided by the sol-gel network with an active-chemistry protection against corrosion provided by corrosion inhibitors and cross-linking agents. Sol-gel coatings, organic–inorganic hybrid materials were prepared by hydrolysis and condensation of (3-glycidyloxypropyl)trimethoxysilane (GPTMS) and tetraethylorthosilane (TEOS) in an ethanol/water solution. This coatings were satisfactorily modified by adding an inhibitor of the corrosion, namely hexahydrate cerium nitrate, and a cross-linking agent, namely tris(trimethylsilyl)phosphite (TMSP). The synergetic effect of these two compounds was evaluated by means of electrochemical characterization. The evolution rate of the hydrolysis-polycondensation reaction was monitored by Fourier-transform infrared spectroscopy and viscosity. Once the hydrolysis-polycondensation rate was reached, sols were deposited on titanium fabricated by powder metallurgy. The morphological characteristics and elemental distribution of the coatings were studied using scanning electrochemical microscopy (SEM). The solid-state of Si-NMR spectroscopy and thermogravimetric analysis (TGA) was employed in order to identify the cross-linking state of the coating by ensuring the creation of enough siloxane bonds. Impedance measurements were carried out to study the effect of cerium and TMSP on the corrosion resistance. It was observed that the coating with additions of cerium presented stable and good barrier features against 5 mM NaCl solution. The synergy between the cerium inhibitor and the TMSP cross-linking agent was found not to exert a positive effect because the electrochemical behaviour was dominated by the phosphorus compound over the cerium. ; The authors acknowledge the financial support from the Regional Government of Madrid through the program MULTIMAT-CHALLENGE (S2013/MIT-2862). The authors acknowledge the financial support from the European Union and Government of Spain through the program RETOSCOLABORACIÓN. RECORD (RTC-2015-3513-S) [i.e. RTC-2015-3513-5]

MAX phases are a promising family of materials for several demanding, high-temperature applications and severe conditions. Their combination of metallic and ceramic properties makes MAX phases great candidates to be applied in energy production processes, such as high temperature heat exchangers for catalytic devices. For their successful application, however, the effect of the processing method on properties such as wear and mechanical behavior needs to be further established. In this work, the mechanical and wear properties of self-synthesized Ti3SiC2 and Cr2AlC MAX phase powders consolidated by different powder metallurgy routes are evaluated. Uniaxial pressing and sintering, cold isostatic pressing and sintering and hot pressing were explored as processing routes, and samples were characterized by analyzing microstructure, phase constitution and porosity. Wear behavior was studied by reciprocating-sliding tests, evaluating the wear rate by the loss of material and the wear mechanism. ; The authors would like to thank the funding provided for this research by the Regional Government of Madrid (Dra. Gral. Universidades e Investigación) through the project P2018/NMT4411 (ADITIMAT-CM), and the Spanish Government through the projects PID2019-106631GB-C43 and RTC2019-007049-4.

The aim of this study was to develop new chrome-free surface pretreatments for AA2024-T3 aluminum alloy. These pretreatments were based on hybrid organic-inorganic sol-gel thin films prepared from mixtures of The aim of this study was to develop new chrome-free surface pretreatments for AA2024-T3 aluminum alloy. These pretreatments were based on hybrid organic–inorganic sol–gel thin films prepared from mixtures of γ -methacryloxypropyltrimethoxysilane (MAPTMS) and tetramethylorthosilicate (TMOS). Di erent MAPTMS/TMOS molar ratios were used for optimizing the physical–chemical characteristics of the sol–gel films. The formulation of a set of these sols was modified by incorporating piperazine (1,4-diazacyclohexane) as a corrosion inhibitor. The resulting sol–gel films were characterized by using Fourier transform infrared spectroscopy (FTIR), liquid-state 29Si nuclear magnetic resonance spectroscopy (29Si-NMR) and viscosity measurements. The corrosion performance of the sol–gel films was analyzed by using electrochemical impedance spectroscopy (EIS) and local electrochemical impedance mapping (LEIM). The characterization techniques indicated that piperazine behaved as a catalyst for the condensation reaction during the formation of the MAPTMS/TMOS organopolysiloxane network and produces an increase of the crosslinking degree of the sol–gel films. EIS and LEIM results showed that piperazine is an e ective corrosion inhibitor, which can be used to enhance the active corrosion protection performance of sol–gel films.-methacryloxypropyltrimethoxysilane (MAPTMS) and tetramethylorthosilicate (TMOS). Di erent MAPTMS/TMOS molar ratios were used for optimizing the physical-chemical characteristics of the sol-gel films. The formulation of a set of these sols was modified by incorporating piperazine (1,4- diazacyclohexane) as a corrosion inhibitor. The resulting sol-gel films were characterized by using Fourier transform infrared spectroscopy (FTIR), liquid-state 29Si nuclear magnetic resonance spectroscopy (29Si-NMR) and viscosity measurements. The corrosion performance of the sol-gel films was analyzed by using electrochemical impedance spectroscopy (EIS) and local electrochemical impedance mapping (LEIM). The characterization techniques indicated that piperazine behaved as a catalyst for the condensation reaction during the formation of the MAPTMS/TMOS organopolysiloxane network and produces an increase of the crosslinking degree of the sol-gel films. EIS and LEIM results showed that piperazine is an e ective corrosion inhibitor, which can be used to enhance the active corrosion protection performance of sol-gel films. ; This research was funded by the Ministry of Economy and Competitiveness of Spain (MAT2015-65445-C2-1-R and MAT2015-70780-C4-2-P Projects), and the Regional Government of Madrid (Project P2018/NMT-4411 ADITIMAT-CM).

Fungal prosthetic-joint infections are rare but devastating complications following arthroplasty. These infections are highly recurrent and expose the patient to the development of candidemia, which has high mortality rates. Patients with this condition are often immunocompromised and present several comorbidities, and thus pose a challenge for diagnosis and treatment. The most frequently isolated organisms in these infections are Candida albicans and Candida parapsilosis, pathogens that initiate the infection by developing a biofilm on the implant surface. In this study, a novel hybrid organo-inorganic sol-gel coating was developed from a mixture of organopolysiloxanes and organophosphite, to which different concentrations of fluconazole or anidulafungin were added. Then, the capacity of these coatings to prevent biofilm formation and treat mature biofilms produced by reference and clinical strains of C. albicans and C. Parapsilosis was evaluated. Anidulafungin-loaded sol-gel coatings were more effective in preventing C. albicans biofilm formation, while fluconazole-loaded sol-gel prevented C. parapsilosis biofilm formation more effectively. Treatment with unloaded sol-gel was sufficient to reduce C. albicans biofilms, and the sol-gels loaded with fluconazole or anidulafungin slightly enhanced this effect. In contrast, unloaded coatings stimulated C. parapsilosis biofilm formation, and loading with fluconazole reduced these biofilms by up to 99%. In conclusion, these coatings represent a novel therapeutic approach with potential clinical use to prevent and treat fungal prosthetic-joint infections. ; This research was funded by MUTUA MADRILEÑA FOUNDATION, grant number 04078/001 and REGIONAL GOVERNMENT OF MADRID through the ADDIMAT PROGRAM, grant number S2018/NMT-4411

This contribution focuses on modifying the composition and surface characteristics of powder metallurgy titanium substrates to improve their wear resistance and to reduce the surface Young's modulus, while maintaining the corrosion resistance and biocompatibility. The modification consists of Mo and TiN coatings produced by colloidal techniques which are deposited by electrophoretic deposition (EPD) or spraying onto green or sintered titanium substrates. The final surface structures are formed during a heat treatment, during which diffusion and consolidation of the layers take place. The surfaces are characterised by XRD, SEM, and micro-indentation; showing diffusion areas of between 40 and 85 microns with clear microstructural changes as well as higher hardness values. ; Funds provided by Spanish Government (program MINECO, ref. MAT2012-38650-C02-01) and Regional Government of Madrid (program MULTIMAT-CHALLENGE, ref. S2013/MIT-2862).

Proceeding of: World PM2016 Congress (New materials and applications: Biomedical applications) ; The aim of this work was the modification of the composition and surface microstructure of powder metallurgy titanium to improve the wear resistance and reduce the elastic modulus while maintaining the corrosion behavior, characteristics needed for biomedical applications. For this purpose, Mo and Nb coatings were produced by colloidal techniques. Stable aqueous suspensions were prepared from micro-sized powder of Mo and Nb particles, deposited onto the powder metallurgy titanium substrates (green or sintered). After a heat treatment to promote the diffusion and the consolidation of the layers, microstructural changes were obtained. In the case of green substrates, the co-sintering process provides a diffusion depth of 85-100 micron. In the as-sintered case, a uniform depth of 40-65 microns was reached. The surfaces were characterised by micro-hardness, corrosion and tribocorrosion testing, and the results showed that hardened surfaces presented lower tendency to corrosion both under static conditions and under sliding. ; Funds were provided by Spanish Government (programme MINECO, ref. MAT2012-38650-C02-01), Regional Government of Madrid (programme MULTIMAT-CHALLENGE, ref. S2013/MIT-2862) and Institute of Álvaro Alonso Barba (IAAB) for the research stay in CMEMS-UMINHO (University of Minho).

The aim of this study was to evaluate the effect of a moxifloxacin-loaded organicinorganic sol-gel with different antibiotic concentration in the in vitro biofilm development and treatment against Staphylococcus aureus, S. epidermidis, and Escherichia coli, cytotoxicity and cell proliferation of MC3T3-E1 osteoblasts; and its efficacy in preventing the prosthetic joint infection (PJI) caused by clinical strains of S. aureus and E. coli using an in vivo murine model. Three bacterial strains, S. epidermidis ATCC 35984, S. aureus 15981, and, E. coli ATCC 25922, were used for microbiological studies. Biofilm formation was induced using tryptic-soy supplemented with glucose for 24 h, and then, adhered and planktonic bacteria were estimated using drop plate method and absorbance, respectively. A 24-h-mature biofilm of each species growth in a 96- well plate was treated for 24 h using a MBECTM biofilm Incubator lid with pegs coated with the different types of sol-gel, after incubation, biofilm viability was estimated using alamrBlue. MC3T3-E1 cellular cytotoxicity and proliferation were evaluated using CytoTox 96 Non-Radioactive Cytotoxicity Assay and alamarBlue, respectively. The microbiological studies showed that sol-gel coatings inhibited the biofilm development and treated to a mature biofilm of three evaluated bacterial species. The cell studies showed that the sol-gel both with and without moxifloxacin were non-cytotoxic and that cell proliferation was inversely proportional to the antibiotic concentration containing by sol-gel. In the in vivo study, mice weight increased over time, except in the E. coliinfected group without coating. The most frequent symptoms associated with infection were limping and piloerection; these symptoms were more frequent in infected groups with non-coated implants than infected groups with coated implants. The response of moxifloxacin-loaded sol-gel to infection was either total or completely absent. No differences in bone mineral density were observed between groups with coated and non-coated implants and macrophage presence lightly increased in the bone grown directly in contact with the antibiotic-loaded sol-gel. In conclusion, moxifloxacinloaded sol-gel coating is capable of preventing PJI caused by both Gram-positive and Gram-negative species ; The authors acknowledge the financial support from the Regional Government of Madrid through the program MULTIMAT-CHALLENGE (S2013/MIT-2862), and from the Mutua Madrileña Foundation (04078/001). JA-C was funded by an FPI grant from the Spanish Ministry of Economics and Competitiveness (BES-2014-069007). AM was funded by grants from Instituto de Salud Carlos III through the "Miguel Servet" program (CP15/00053). DR was funded by a grant from the Fundación Conchita Rábago

Invited keynotes paper from EUROPM2017, Milan. ; This work focuses on the evaluation of modified surfaces on Ti produced by powder metallurgy. These newly designed surface modifications are achieved by deposition and diffusion of a stable aqueous suspension prepared in one case from micro-sized Nb powder (Ti beta-stabilizer element) and in another case from Nb plus the addition of ammonium chloride, NH4Cl, (thermo-reactive diffusion process). Different design parameters such as diffusion element (Nb or Mo), state of the Ti substrate (green or sintered) and the treatment process (diffusion or thermo-reactive diffusion) lead to all the surface-modified materials, GreenTi-Nb, SintTi-Nb and Ti-Nb-NH4Cl, GreenTi-Mo, SintTi-Mo and Ti-Mo-NH4Cl. The modified Ti surfaces present a gradient in composition and microstructure (beta / alpha+beta / alpha phases) resulting in an improvement in some of their mechanical properties: (1) higher micro-hardness in all the modified materials and (2) lower elastic modulus (more similar to that of the human bone) in those without NH4Cl. ; The authors would like to thank the funding provided for this research by the Regional Government of Madrid (program MULTIMAT-CHALLENGE-CM, ref. S2013/MIT- 2862), and by the Ministry of Economy and Competitiveness of Spain (program MINECO, ref. PCIN-2016-123 and Ramón y Cajal contract RYC-2014-15014).

ERECON (2014) Strengthening the European rare earths supply chain: Challengesand policy options. Kooroshy, J., G. Tiess, A. Tukker, and A. Walton (eds.). ; Policy recommendations:1.Maintaining and strengthening the European Rare Earth Elements (REE) skills and knowledge base through research funding, science and technology education and international cooperation.Without cutting-edge research and technical expertise, a European high-tech REE industry cannot flourish. The EC and Member States should support funding for research grants, scholarships, and training networks, and enhance European and international cooperation through coordinated calls, researcher exchanges, and joint high-level conferences.2.Creating the basis for informed decision-making on REEs through a European Critical Materials Observatory.Mapping and monitoring of REE supply chains is necessary for informed decision-making. Expertise in Europe could be pooled in a virtual Critical Materials Observatory that provides the public with consistent and authoritative knowledge on REEs (e.g., information on advanced exploration projects, prices, key demand and supply trends, and the urban mine potential).3.Support promising technologies through funding industry-led pilot plants for innovative HREE processing.The EC, industry and Member States should accelerate the commercialization and scaling up of key technologies through co-financing industry-led pilot plants. This should include pilots for REE recovery from heavy rare earths-rich minerals, direct-alloy recycling routes, process and sensor equipment for REE recycling, and REE recovery from industrial residues.4.Levelling the playing field for European HREE exploration through co-funding for prefeasibility and bankable feasibility studies.Support from federal and state governments in the U.S., Australia and Canada has played a critical role in advancing project exploration. The EC and Member States should evaluate possibilities for supporting the extensive R&D necessary for pre-feasibility and bankable feasibility studies, to avoid high quality deposits in Europe simply going unexplored.5.Making waste management REE-friendly through eco-design, incentive schemes for collecting priority waste products, and streamlining policy and waste regulation.The EC and Member States should promote recycling-friendly design to help identify and recover REE components in waste more easily. Potential incentives for stimulating REE waste collection should be evaluated and the shipment of REE wastes should be facilitated. More consistency should also be created in implementing and applying existing waste regulations.6.Boost supply security and de-risk strategic REE investment cases through enhanced cooperation among European end-users and other stakeholders.Leading end-users should engage in strategic cooperation across industry and with governments. This could include setting up a voluntary European 'critical raw materials fund', establishing a 'European Resource Alliance' similar to the German Rohstoffallianz, and convening a high-level taskforce to examine ways in which public funding could support resilient REE supply chains for Europe.