CIDETEC-Artikuluak;;CIDETEC-Artículos
http://hdl.handle.net/10810/14958
2024-03-29T00:13:50ZEffect of Post-Processing Treatment on Fatigue Performance of Ti6Al4V Alloy Manufactured by Laser Powder Bed Fusion
http://hdl.handle.net/10810/62682
Effect of Post-Processing Treatment on Fatigue Performance of Ti6Al4V Alloy Manufactured by Laser Powder Bed Fusion
Mancisidor, Ane Miren; García-Blanco, María Belén; Quintana, Iban; Arrazola, Pedro José; Espinosa, Elixabete; Cuesta, Mikel; Albizuri Irigoyen, Joseba; Garciandia, Fermin
Fatigue properties of parts are of particular concern for safety-critical structures. It is well-known that discontinuities in shape or non-uniformities in materials are frequently a potential nucleus of fatigue failure. This is especially crucial for the Ti6Al4V alloy, which presents high susceptibility to the notch effect. This study investigates how post-processing treatments affect the mechanical performance of Ti6Al4V samples manufactured by laser powder bed fusion technology. All the fatigue samples were subjected to a HIP cycle and post-processed by machining and using combinations of alternative mechanical and electrochemical surface treatments. The relationship between surface properties such as roughness, topography and residual stresses with fatigue performance was assessed. Compressive residual stresses were introduced in all surface-treated samples, and after tribofinishing, roughness was reduced to 0.31 ± 0.10 µm, which was found to be the most critical factor. Fractures occurred on the surface as HIP removed critical internal defects. The irregularities found in the form of cavities or pits were stress concentrators that initiated cracks. It was concluded that machined surfaces presented a fatigue behavior comparable to wrought material, offering a fatigue limit superior to 450 MPa. Additionally, alternative surface treatments showed a fatigue behavior equivalent to the casting material.
2023-06-22T00:00:00ZEnhanced Biodegradability in Soil of Chicken Feather by Steam Explosion for Potential Application in Agricultural Biodegradable Plastics
http://hdl.handle.net/10810/62459
Enhanced Biodegradability in Soil of Chicken Feather by Steam Explosion for Potential Application in Agricultural Biodegradable Plastics
Vadillo, Julen; Montes, Sarah; Grande, Hans-Jürgen; Verstichel, Steven; Almqvist, Jonna; Wrzesniewska-Tosik, Krystyna
Feather waste is a major issue from an economic and environmental point of view. Even
though there are already routes for the valorisation of feathers into fertilisers and feather meal, these
are considered to have low added value. For more attractive applications, for example in agricultural
biodegradable plastics, higher and faster degradability in soil is required. To face this challenge
alternative approaches to accelerate biodegradation and disintegration processes are needed. In this
context, steam explosion appears as an effective technology to modify the structure of feather and
improve its soil degradability. In this work, chicken feathers were treated by steam explosion and the
effect of treatment on their structure and physico-chemical and thermal properties were evaluated.
Finally, the effect of the process conditions on the disintegration and biodegradation in soil of feathers
was also investigated, finding an increased degradation in soil of steam explosion treated feathers.
These results open up the possibilities of using feather waste as a component for environmentally
friendly agricultural bioplastics that can be degraded in-situ in soil.
2023-09-08T00:00:00ZA practical perspective on the potential of rechargeable Mg batteries
http://hdl.handle.net/10810/61153
A practical perspective on the potential of rechargeable Mg batteries
Blázquez, J. Alberto; Maça, Rudi R.; Leonet, Olatz; Azaceta, Eneko; Mukherjee, Ayan; Zhao-Karger, Zhirong; Li, Zhenyou; Kovalevsky, Aleksey; Fernandez-Barquin, Ana; Mainar, Aroa R.; Jankowski, Piotr; Rademacher, Laurin; Dey, Sunita; Dutton, Sian E.; Grey, Clare P.; Drews, Janina; Hacker, Joachim; Danner, Timo; Latz, Arnulf; Sotta, Dane; Palacin, M. Rosa; Martin, Jean-Frederic; García Lastra, Juan Maria; Fichtner, Maximilian; Kundu, Sumana; Kraytsberg, Alexander; Ein-Eli, Yair; Noked, Malachi; Aurbach, Doron
Emerging energy storage systems based on abundant and cost-effective materials are key to overcome the global energy and climate crisis of the 21st century. Rechargeable Magnesium Batteries (RMB), based on Earth-abundant magnesium, can provide a cheap and environmentally responsible alternative to the benchmark Li-ion technology, especially for large energy storage applications. Currently, RMB technology is the subject of intense research efforts at laboratory scale. However, these emerging approaches must be placed in a real-world perspective to ensure that they satisfy key technological requirements. In an attempt to bridge the gap between laboratory advancements and industrial development demands, herein, we report the first non-aqueous multilayer RMB pouch cell prototypes and propose a roadmap for a new advanced RMB chemistry. Through this work, we aim to show the great unrealized potential of RMBs.
2023-04-14T00:00:00ZHigh performance carbon free bifunctional air electrode for advanced zinc-air batteries
http://hdl.handle.net/10810/60633
High performance carbon free bifunctional air electrode for advanced zinc-air batteries
Ramos Mainar, Aroa; Blázquez, José Alberto; Frattini, Domenico; Enterría, Marina; Ortiz-Vitoriano, Nagore; Urdampilleta, Idoia; Grande, Hans-Jürgen
Secondary zinc-air batteries (ZABs) offer a promising alternative for the future of sustainable energy storage. However, the current capability of secondary ZABs is far from satisfactory. The limitations for achieving high reversibility are mainly related to the bifunctional air electrodes as it severely hampers practical applications and commercialization of secondary ZABs. Many efforts have been devoted to the development of efficient and corrosion resistant bifunctional electrocatalysts towards oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). In ZABs, carbon is commonly used as conductive additive, however, it has been observed that carbon materials are not resistant to the high positive voltages applied in electrical recharge. In this work, the use of metallic nickel as alternative conductive additive in bifunctional air electrodes is explored and compared with carbon nanotubes (CNT). We demonstrate that the chemical resistance of CNT does not limit the electrode performance; but the density of the additive as well as its interaction with the active material is crucial for achieving long cycle life. The use of Ni as conductive agent in secondary ZABs boosted the cycle life by delivering more than 2,400 cycles, in contrast to the 88 cycles delivered by the analogous carbon-based battery.
2023-04-01T00:00:00Z