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Percorrer ENERGIA por Objetivos de Desenvolvimento Sustentável (ODS) "09:Indústria, Inovação e Infraestruturas"
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- Comparison of the corrosion of ferritic and austenitic stainless steel (AISI 430 and AISI 316L) with LiNaK carbonate salts for thermal energy storage in CSP/CST applicationsPublication . Gil, Mafalda; Pedrosa, Fátima; Paiva Luís, Teresa; Figueira Vasques, Isabel; Oliveira, Fernando; Cunha Diamantino, TeresaABSTRACT: This study focuses on the corrosion rates and mechanisms of two stainless steels, austenitic AISI 316L and ferritic AISI 430, in contact with a eutectic mixture of LiNaK carbonates in long-term tests at 650 degrees C. The selection of these two stainless steels was based on their differences, both in their intrinsic characteristics and in the cost associated with each one. The research also underscores the importance of optimizing the descaling methods used to evaluate the corrosion rate. Corrosion rates were measured gravimetrically according to ISO 17245:2015, revealing an asymptotic behavior for both steels, with AISI 430 with a corrosion rate of 237 f 21 mu m and AISI 316L of 151 f 13 mu m after 2000 h of testing. Corrosion mechanisms were analyzed using SEM/EDS, GDOES, and XRD techniques, which identified well-defined oxide layers with varying compositions. Given the observed corrosion mechanisms and its lower cost, AISI 430 steel seems to have great applicability in CSP/CST plants, provided it is paired with an appropriate protective coating.
- Detection of corrosion on silvered glass reflectors via image processingPublication . Wiesinger, Florian; Baghouil, Sarah; Le Baron, Estelle; Collignon, Romain; Santos, Filipa; Cunha Diamantino, Teresa; Catarino, Isabel; Facão, Jorge; Ferreira, Cristina; Páscoa, Soraia; Sutter, Florian; Fernández-García, Aránzazu; Wette, JohannesABSTRACT: A novel characterization technique based on image analysis is presented, intended to complement state-of-the-art reflectometer measurements. The technique is developed by experts from different laboratories (OPAC, AGC, CEA and LNEG), which subsequently conduct two Round Robin experiments on corroded solar reflectors for validation. Regarding the inter-comparability, it is found that parameters like the corrosion spot density or the penetration maximum on coated edges exhibit an average coefficient of variation of 62.6 % and 54.9 %. Better agreement is found for parameters like the total corroded area and the maximum edge corrosion penetration, with coefficients of variation of 14.3 % and 13.4 %, respectively. The developed methodology is further applied during a 68-month lasting outdoor exposure campaign of two types of solar reflectors at two representative sites, one exhibiting corrosivity class C2 and the other C3. On the commercial coating RL1, a total corroded area of 59 mm2 and 426 mm2 is measured after the outdoor exposure on the C2 and the C3 site, respectively, while on the novel low-lead coated reflector RL3 corresponding values are 280 mm2 and 1308 mm2. This shows the superior quality of the coating RL1 in terms of corrosion resistance. Furthermore, the analysis highlights the importance of proper edge sealing for corrosion protection, since corrosion penetration is increased by a factor between 1.3 and 4.0 if the edges are unprotected. The reflectance decrease after the outdoor exposure is regarded as negligible (0.000 - 0.005), thus not permitting any of the conclusions that are made from the novel image analysis technique.
- Development of lightweight Sandwich Composites with improved Reaction to Fire and UV resistance for Double Curvature Façade Panels [Poster]Publication . Rocha, Helena; Vasconcelos, Miguel; Malheiro, Joana; Nascimento, António; Paula, Delves; Simões, Nuno; Barreiros, Maria Alexandra; Cunha Diamantino, Teresa; Ferreira, Cristina; Gonçalves, Diana; Antunes, PauloABSTRACT: Buildings with double curvature façades can be aesthetically pleasing, being capable of enchanting both architects and the general public Though, manufacturing of such façades can be a challenge in both technologic and economic terms Traditional molding technologies demand a unique mold for each panel geometry resulting in substantial costs related to raw materials and storage space, and long lead times for designing and manufacturing. A reconfigurable multipoint mold has been identified to solve this issue, where an array of moving pins can have their height quickly adjusted to form the required shape and molding surface. Another present technological challenge is the highly demanding fire resistance requirements Certain European countries require that public and civil buildings comply with the highest grades of EN 13501 standard, A 2 s 1 d 0 and B, s 1 d 0. That is a serious constraint when developing lightweight sandwich fiber reinforced polymer FRP composites, as polymeric materials do not naturally present good reaction to fire behavior Furthermore, the polymeric raw materials should present suitable processability with the reconfigurable multipoint mold and supporting processing equipment and allow the manufacturing of sandwich structures Sandwich composites structures are lightweight solutions with high stiffness, consisting of two composite laminate faces, separated by a lightweight core material, commonly made of foam or honeycomb.
- Dielectric UV filters for protection of fire-resistant glass based on intumescent layersPublication . Silva, Ricardo Magno Lopes; Hashim, Hurraira; Roy, Deepto; Oliveira Fernandes, Carolina; Oliveira, Kevin; Leitão Pinheiro, Xavier Alexandre; Esteves, M. Alexandra; Capelo, Anabela; Donato, Mariana; Oliveira, Fernando; Ferreira, Cristina; Alves, Isabel N.; Cunha Diamantino, Teresa; Barreiros, Maria Alexandra; Rocha, Jorge; Passos Teixeira, Jennifer; Salomé, PedroABSTRACT: Structures such as OLEDs, perovskite solar cells, intumescent glasses, and other components in modern devices and buildings contain materials suscep-tible to degradation when exposed to UV radiation, requiring protection to with-stand outdoor environmental conditions. In this work, multilayer coating config-ured as a Bragg Reflector on glass is employed as spectral filtering to protect the intumescent component of fire-resistant glass from degradation due to prolonged UV solar radiation exposure. By alternating low-n (SiO2)/high-n (TiO2) dielectric layers through spin-coating, precise control over film thickness could be achieved, allowing the fabrication of thin (<700 nm) UV filters with high trans-mission of visible sunlight – 88% of the 780 to 380 nm wavelength range – while reflecting almost all the incident UV – 90% of the wavelength below 380nm. Using relatively simple techniques, high precision coating was successfully achieved, resulting in an effective UV radiation protective barrier applied to en-hance the durability of the components in fire-resistant glass.
- Dielectric UV filters for protection of fire-resistant glass based on intumescent layers [Comunicação oral]Publication . Silva, Ricardo Magno Lopes; Hashim, Hurraira; Roy, Deepto; Oliveira Fernandes, Carolina; Oliveira, Kevin; Leitão Pinheiro, Xavier Alexandre; Esteves, M. Alexandra; Capelo, Anabela; Donato, Mariana; Oliveira, Fernando; Ferreira, Cristina; Alves, Isabel N.; Cunha Diamantino, Teresa; Barreiros, Maria Alexandra; Rocha, Jorge; Passos Teixeira, Jennifer; Salomé, Pedro
- Enhancing Corrosion Resistance of Al-Mg Alloys through Biomineralization [Resumo]Publication . Marques, Maria João; Fori, Benoit; Mercier, Dimitri; Seyeux, Antoine; Zanna, Sandrine; Marcus, Philippe; BASSEGUY, RegineABSTRACT: In recent decades, new emerging microbiological technologies have been studied, based on the recognition that microorganisms can inhibit corrosion by different mechanisms, the so-called MICI (microbiologically influenced corrosion inhibition), opening up different lines of research. In this context, biomineralization has been attracting the attention of researchers, with an increasing number of studies showing that different types of mineralized layers formed on metal surfaces can reduce the risk of corrosion.
- Exploring Marine Biomineralization on the Al-Mg Alloy as a Natural Process for In Situ LDH Growth to Improve Corrosion ResistancePublication . Marques, Maria João; Mercier, Dimitri; Seyeux, Antoine; Zanna, Sandrine; Tenailleau, Christophe; Duployer, Benjamin; Jeannin, Marc; Marcus, Philippe; Basséguy; BASSEGUY, RegineABSTRACT: This study provides a detailed characterization of the AA5083 aluminum alloy, surface, and interface over 6 months of immersion in seawater, employing techniques such as SEM/EDX, GIXRD, mu-Raman and XPS. The purpose was to evaluate the evolution of the biomineralization process that occurs on the Al-Mg alloy. By investigating the specific conditions that favor the in situ growth of layered double hydroxide (LDH) during seawater immersion as a result of biomineralization, this research provides insights into marine biomineralization, highlighting its potential as an innovative and sustainable strategy for corrosion protection.
- Fire-resistant materials: characterization and thermal behavior of intumescent gels for fire resistant glass [Poster]Publication . Donato, Mariana; Esteves, M. Alexandra; Capelo, Anabela; Oliveira, Fernando; Ferreira, Cristina; Alves, Isabel N.; Morgado, Vanessa; Correia, Jose B.; Teixeira, Jennifer P.; Oliveira Fernandes, Carolina; Silva, Ricardo Magno Lopes; Rocha, Jorge; Salomé, Pedro; Cunha Diamantino, Teresa; Barreiros, Maria Alexandra
- La biominéralisation comme bioinspiration pour le développement de solutions anti-corrosion [Resumo]Publication . BASSEGUY, Regine; Marques, Maria JoãoRÉSUMÉ: Dans le domaine de la corrosion, la nature se révèle être une source d’inspiration pour développer de nouveaux concepts de protection verts. En effet, il est largement reconnu que les micro-organismes sont capables non seulement d’accélérer la orrosion mais ils peuvent également l'inhiber et/ou protéger les matériaux qu’ils colonisent [1]. Ce constat a ainsi conduit à proposer des stratégies à base microbienne pour l'inhibition de la corrosion des métaux. En particulier, le processus de biominéralisation à la surface des matériaux, tels que les pierres, le béton et divers métaux, a récemment été considéré comme une nouvelle approche respectueuse de l'environnement pour produire des couches protectrices [2-3]. Jusqu’à peu, la majorité des publications concernaient les aciers, matériaux historiquement utilisés dans les infrastructures. Au cours des dernières années, de nouveaux matériaux tels que les alliages d'aluminium, sont apparus sur le marché comme des alternatives possibles. Dans le cas spécifique de l'alliage Al-Mg, souvent utilisé dans les applications marines, peu d'études ont évalué l'influence de la biominéralisation sur la corrosion [4-6]. L'objectif de cette présentation est de montrer, à travers deux études de cas, comment la précipitation minérale influencée par l’activité microbienne sur les matériaux métalliques peut être envisagée comme une nouvelle approche pour le développement de solutions anti-corrosion.
- NEWS4CSP Project: New Coatings Approaches to Protect Metallic Materials From Heat Transfer FluidsPublication . Cunha Diamantino, Teresa; Pedrosa, Fátima; Paiva Luís, Teresa; Ferreira da Silva, Eduardo; Gonçalves, Francisco; Monteiro, Renato; Cardoso, JoãoABSTRACT: The efficiency of Concentrated Solar Power technologies increases with the opera-tion temperature of the power block, which can be achieved using advanced power cycles operating at temperatures ≥650°C. Molten Salt (MS) based HTF have been facing critical chal-lenging issues of severe corrosion and lower specific heat capacity. This paper aims to present the NEWS4CSP project to the CSP scientific community, highlighting the main concepts being pursued and the preliminary results obtained regarding the application of new coatings to in-crease the anticorrosive protection of structural materials in contact with MS. Two different types of powder coatings (nickel and cobalt alloys) were applied to AISI 430 stainless steel using two coating technologies: High Velocity Oxy-Fuel (HVOF) and Laser Cladding (LC). LC proved to be the most suitable technique of these two coating application technologies. The Co-Cr coating alloy showed good anticorrosive behaviour even after 3000 h of testing. The obtained results are very promising, nevertheless, more studies are needed to optimise its application by LC. These include optimizing the thickness and chemical composition, as well as gaining a deeper understanding of the degradation mechanisms and whether this behaviour is maintained over longer periods.