http://hdl.handle.net/10498/19475 Sat, 07 Nov 2026 22:56:58 GMT 2026-11-07T22:56:58Z http://hdl.handle.net/10498/39194 Valorización de residuos sólidos urbanos poliméricos en materiales híbridos de poliuretano para aislamiento térmico en edificación Silva García, Blanca Gema; Terrones Saeta, Juan María; Sales Lérida, David Este trabajo evalúa la viabilidad técnica, ambiental y económica de valorizar residuos poliméricos urbanos de LDPE (rechazo final de RSU) y HDPE (envases post-consumo) incorporándolos como particulado en una matriz de poliuretano rígido para fabricar paneles aislantes térmicos en edificación. Se elaboraron espumas de PU con 10–20 % de residuo mediante moldeo y se caracterizaron por densidad y propiedades térmicas (conductividad λ y R-value) a distintas temperaturas; además se evaluó la lixiviación mediante TCLP (EPA 1311) y la huella de carbono. Los resultados muestran que con 10–20 % de LDPE se mantiene una λ baja y R-values competitivos, mientras que el HDPE incrementa la densidad y empeora el comportamiento aislante a igual fracción. Contenidos altos (≥40 %) no se recomiendan por el aumento de densidad y conductividad. El análisis ambiental indica reducciones aproximadas del 40 % frente a la incineración al reintroducir el residuo en el ciclo de materiales, mostrando el potencial de esta vía dentro de la economía circular. Abstract de congreso publicado en el “Libro de abstracts” de RH2EDIN (octubre 2025), abstract nº 59, pp. 148–150. Wed, 01 Oct 2025 00:00:00 GMT http://hdl.handle.net/10498/39194 2025-10-01T00:00:00Z http://hdl.handle.net/10498/38476 SOM-SEM-EDS identification of tool wear mechanisms in the dry-machining of aerospace titanium alloys Álvarez Alcón, Miguel; Gómez Parra, Álvaro; Salguero Gómez, Jorge; Batista Ponce, Moisés; Huerta Gómez de Merodio, Milagros; Marcos Bárcena, Mariano Titanium based alloys, mainly UNS R56400 (Ti6Al4V), are increasingly being applied in the airship building industry due to its excellent physicochemical properties. Machining operations are usually required in the manufacturing processes of Ti based aerospace structural elements. However, high reactivity of Ti provokes a quick tool wear. So, in order to reach an economically acceptable production level, it is necessary to minimize the costs associated to tool wear. In this work, Scanning Electron Microscopy (SEM), Stereoscopic Optical Microscopy (SOM) and Energy Dispersive Spectroscopy (EDS) have been used for both analysing and identifying secondary adhesion mechanisms that are taking place when an aeronautical titanium alloy is machined. Special severe cutting conditions have been applied. Thus, titanium alloy have been dry machined with TiN coated WC-Co tools. Results obtained have shown that tool wear is controlled by a secondary adhesion mechanism, which presents two stages. A first stage is constituted by a TiOx multi-film formed onto the tool surfaces. A second step involves the mechanical adhesion of the alloy material to those surfaces. When this material is removed, tool particles are dragged off causing tool wear. Fri, 01 Jan 2010 00:00:00 GMT http://hdl.handle.net/10498/38476 2010-01-01T00:00:00Z http://hdl.handle.net/10498/38472 Low environmental impact machining processes of composite materials applied to the aerospace sector Álvarez Alcón, Miguel; Batista Ponce, Moisés; Salguero Gómez, Jorge; Sánchez Carrilero, Manuel; Marcos Bárcena, Mariano In the last decades, thecnologically innovative processes performed in advanced materials such as Carbon Fibre (CF) and Metal Matrix Composites (MMC) have continuously increased because of these materials find increasingle applications in the most of the industrial sector, particulary in aeronautical industry. This is caused by their excellent relationship weight/machanical properties. Although there is high trend to apply and develop non-conventional technologies and methods for machinig CF and MMC, other common machining processes are commonly applied for working these materials. Thus, in aeronautical industry, mechanical drilling processes are usually applied for preparing the manufactured elements to be assembled. However, drilling of CF based materialscan carry on troubes related to a loss of Surface finishing quality and/or quick and high toolo wear. This work reports on the results about an evaluation process of the Surface quality of drilled CF samples as a funcition of the cutting conditions and the tool materials. Fri, 01 Jan 2010 00:00:00 GMT http://hdl.handle.net/10498/38472 2010-01-01T00:00:00Z http://hdl.handle.net/10498/36616 Development of a chemical model to predict the doses of calcium sulfate and tartaric acid to acidify musts in Sherry area Gómez, J.; Palacios Santander, José María; Lasanta Melero, Cristina; Cubillana Aguilera, Laura; Arnedo, R.; Casas, J. A.; Amilibia, B.; LLoret, I. Calcium sulfate is normally used as a complementary acidifier combined with tartaric acid. The doses corresponding to each one depend on the desired reduction of pH and on the composition of musts. However, considering that there are several interrelated chemical equilibria implied (tartaric acid dissociation, calcium tartrate and potassium bitartrate precipitation, etc.), it is not easy to predict the effect on pH of a mixed tartaric acid and calcium sulfate addition and to determine the necessary doses to reach the final pH required by the winemaker. In a model previously developed by the authors, the prediction of pH after an acidification was properly achieved. On the contrary, in the same model the prediction of the necessary doses of acidifiers to achieve a desired pH have higher errors due to some parameters, as pH and pK, are found as exponential functions in the equations. This work develops and verify the necessary corrections to the models so that appropriate predictions of the doses are obtained. With these corrections, prediction errors of less than 5% were obtained for all doses of acidifiers, confirming the good comprehension of the chemical equilibria involved in this practice. Sun, 01 Jan 2017 00:00:00 GMT http://hdl.handle.net/10498/36616 2017-01-01T00:00:00Z