Multilayer and particle size-graded YSZ coatings obtained by plasma spraying of micro- and nanostructured feedstocks

This work was supported by the Spanish Ministry of Science and Innovation (Project MAT2012-38364-C03) and the Research Promotion Plan of Universitat Jaume I, action 3.1 (Ref. PREDOC/2009/10), and it has been co-funded by the European Regional Development Fund (ERDF). The authors also thank the SCIC of Universitat Jaume I for the FEG-SEM observationsCarpio, P.; Bannier, E.; Salvador Moya, MD.; Benavente Martínez, R.; Sanchez Vilches, E. (2014). Multilayer and particle size-graded YSZ coatings obtained by plasma spraying of micro- and nanostructured feedstocks. Journal of Thermal Spray Technology. 23(8):1362-1372. https://doi.org/10.1007/s11666-014-0143-9S13621372238D.R. Clarke and S.R. Phillpot, Thermal Barrier Coatings Materials, Mater. Today, 2005, 8, p 22-29N.P. Patdure, M. Gell, and E.H. Jordan, Thermal Barrier Coatings for Gas-Turbine Engine Applications, Science, 2002, 296, p 280-284L. Pawlowski, Finely Grained Nanometric and Submicrometric Coatings by Thermal Spraying: A Review, Surf. Coat. Technol., 2008, 205(43), p 18-28R.S. Lima and B.R. Marple, Thermal Spray Coatings Engineered from Nanostructured Ceramic Agglomerated Powders for Structural, Thermal Barrier and Biomedical Applications: A Review, J. Therm. Spray Technol., 2007, 16(1), p 40-63P. Fauchais, G. Montavon, R.S. Lima, and B.R. Marple, Engineering a New Class of Thermal Spray Nano-Based Microstructures from Agglomerated Nanostructured Particles, Suspensions and Solutions: An Invited Review, J. Phys. D, 2011, 44(9), 93001, p 1-131M. Gell, E.H. Jordan, Y.H. Sohn, D. Goberman, L. Shaw, and T.D. Xiao, Development and Implementation of Plasma Sprayed Nanostructured Ceramic Coatings, Surf. Coat. Technol., 2001, 146-147, p 48-54R.S. Lima and B.R. Marple, Nanostructured YSZ Thermal Barrier Coatings Engineered to Counteract Sintering Effects, Mater. Sci. Eng. A, 2008, 485, p 182-193H. Chen, X. Zhou, and C. Ding, Investigation of the Thermomechanical Properties of a Plasma-Sprayed Nanostructured Zirconia Coating, J. Eur. Ceram. Soc., 2003, 23, p 1449-1455K.A. Khor and Y.W. Gu, Thermal Properties of Plasma-Sprayed Graded Thermal Barrier Coatings, Thin Solid Films, 2000, 372, p 104-113A.M. Limarga, T.S. Widjajab, and T.H. Yip, Mechanical Properties and Oxidation Resistance of Plasma-Sprayed Multilayered Al2O3/ZrO2 Thermal Barrier Coatings, Surf. Coat. Technol., 2005, 197, p 93-102X. Chen, Y. Zhao, X. Fan, Y. Liu, B. Zou, Y. Wang, H. Ma, and X. Cao, Thermal Cycling Failure of New LaMgAl11O19/YSZ Double Ceramic Top Coat Thermal Barrier Coating Systems, Surf. Coat. Technol., 2011, 205, p 3293-3300G. Mauer, M.O. Jarligo, D.E. Mack, and R. Vassen, Plasma-Sprayed Thermal Barrier Coatings: New Materials, Processing Issues and Solutions, J. Therm. Spray Technol., 2013, 22(5), p 647-658A. Portinha, V. Teixeira, J. Carneiro, J. Martins, M.F. Costa, R. Vassen, and D. Stoever, Characterization of Thermal Barrier Coatings with a Gradient in Porosity, Surf. Coat. Technol., 2005, 195, p 245-251M. Vicent, E. Sánchez, G. Mallol, and R. Moreno, Study of Colloidal Behaviour and Rheology of Al2O3-TiO2 Nanosuspensions to Obtain Free-Flowing Spray-Dried Granules for Atmospheric Plasma Spraying, Ceram. Int., 2013, 39(7), p 8103-8111F. Müller, W. Peukert, R. Polke, and R. Stenger, Dispersing Nanoparticles in Liquids, Int. J. Miner. Process., 2000, 74, p S31-S34M. Vicent, E. Bannier, R. Moreno, M.D. Salvador, and E. Sánchez, Atmospheric Plasma Spraying Coatings from Alumina-Titania Feedstock Comprising Bimodal Particle Size Distributions, J. Eur. Ceram. Soc., 2013, 33, p 3313-3324C.W. Kang and H.W. Ng, Splat Morphology and Spreading Behaviour due to Oblique Impact of Droplets onto Substrates in Plasma Spray Coating Process, Surf. Coat. Technol., 2006, 200, p 5462-5477Y. Zeng, S.W. Lee, L. Gao, and C.X. 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Alumina-zirconia coatings obtained by suspension plasma spraying from highly concentrated aqueous suspensions

[EN] Suspension plasma spraying (SPS) deposition represents an innovative technique to produce coatings that exhib- it improved properties. However, the key to obtain coatings with superior functional properties relies on the in- vestigation of the suspensions as starting materials. For this reason, the present work deals with the suspension preparation for SPS process and its influence on the resulting coatings. Laboratory-prepared 60/40 wt% alumina-zirconia suspensions were concentrated to avoid energy loss and were then successfully deposited by SPS technique. The liquid used was water instead of ethanol due to economical, environmental and safety reasons. The preparation of the suspension plays an important role in SPS process since stable and well-dispersed water suspensions are difficult to obtain. For this reason, colloidal behaviour characterisation of the starting particles as well as rheological optimisation of the feedstock suspensions was ad- dressed in this research. Suspensions with different solid loadings (up to 30 vol.% or 72 wt%) were deposited using several spraying dis- tances. All coatings displayed a bimodal microstructure consisting in partially melted zones surrounded by a fully melted matrix. α-Al2O3 and t′-ZrO2 constituted the main crystalline phases, but differences in the microstructure and properties of the coatings were observed. From these results, some relations between starting suspension and spraying parameters with coating characteristics were found. Thus the optimal spraying distance becomes shorter when the suspension solid loading increases.This work has been supported by the Spanish Ministry of Economy and Competitiveness, MINECO (project MAT2015-67586-C3-R). M.D. Salvador thanks CAPES – Programa Ciências sem Fronteiras (Brazil) for the concession of a PVE project N° A086/2013. A. Borrell acknowledges the MINECO for her Juan de la Cierva-Incorporación contract (IJCI-2014- 19839) and the Program to Support Research and Development (PAID00-15) of the Universitat Politècnica de València.Carpio-Cobo, P.; Salvador Moya, MD.; Borrell Tomás, MA.; Sanchez Vilches, E.; Moreno, R. (2016). Alumina-zirconia coatings obtained by suspension plasma spraying from highly concentrated aqueous suspensions. Surface and Coatings Technology. 307:713-719. https://doi.org/10.1016/j.surfcoat.2016.09.060S71371930

Effect of quartz particle size on the mechanical behaviour of porcelain tile subjected to different cooling rates

Porcelain tile is a high-performance ceramic tile, in which quartz is a major compositional component. After the firing cycle, macroscopic residual stresses develop in the product as a result of rapid cooling. Further, during cooling, the presence of quartz particles also increases natural flaw size. Both phenomena significantly affect the product's mechanical behaviour. This study examines the effect of quartz particle size on the mechanical behaviour of porcelain tile subjected to two very different cooling rates: a rapid or a slow cooling rate. A series of porcelain tile compositions were designed for this purpose, in which quartz particle size was varied. The mechanical behaviour of the sintered pieces was evaluated on the basis of linear elastic fracture mechanics. It was verified that, in the slowly cooled material, the modulus of elasticity and fracture energy increased, and natural flaw size decreased as quartz particle size decreased. However, fracture energy also diminished in pieces that contained excessively small particles, with an advanced state of dissolution. For the rapidly cooled material, though the larger sized quartz particles debonded at higher temperatures owing to thermal stress, their presence, even in small quantities, contributed to natural flaw growth. The lower fracture energy associated with this last type of piece also favours this phenomenon

Analysis of the development of microscopic residual stresses on quartz particles in porcelain tile

This paper examines the development of microscopic residual stresses on quartz particles in porcelain tile using the XRD technique. The study was conducted with a typical porcelain tile composition consisting of sodium feldspar, kaolin, and quartz, using quartzes with different particle sizes. The methodology used, based on determining the volume strain of the quartz unit cell, allowed a residual stress value equivalent to the entire particle and not just to a given crystalline plane to be obtained. The linear thermal expansion measurements indicated that, for all test compositions, the quartz in the mixture contributes to a thermal expansion coefficient comparable to the expansion of its c-lattice parameter. When this information was taken into account in the theoretical estimation of microscopic residual stress, the results were verified to be consistent with the experimental measurements

Puesta en marcha de plan de actuación en respuesta a prescripciones eur- ace® para la formación y evaluación de competencias transversales en las ingenierías del ámbito industrial de la Universitat Jaume I

Comunicación presentada en la VI Jornada Nacional sobre Estudios Universitarios, , II Taller de Innovación Educativa, Castelló de la Plana, 9 y 10 de noviembre de 2017.Los grados en ingenierías del ámbito industrial de la Universitat Jaume I (Grado en Ingeniería en Tecnologías Industriales, Ingeniería Mecánica, Ingeniería Eléctrica e Ingeniería Química) han participado recientemente en el programa acredita plus de aneca para la renovación de la acreditación y la solicitud del reconocimiento del sello eur-ace® de la agencia enaee. Este proceso ha resultado favorable en tanto en cuanto se ha renovado la acreditación en los mencionados títulos y se ha recono-cido el sello de calidad en programas de ingeniería, eur-ace®, aunque con ciertas prescripciones. Los cuatro títulos en la Universitat Jaume I cuentan con un porcentaje de compartición de créditos importante, especialmente en primeros cursos, y están dotados de mecanismos de coordinación, garantía de calidad y apoyo por parte de los diferentes servicios comunes de la universidad. Las prescripciones recibidas fueron diferentes entre los grados en algunos aspectos, aunque una de las propuestas de me-jora fue común a todos ellos: el aseguramiento de que todos los estudiantes adquieren las competencias transversales del modelo enaee. Los cuatro grados se enfrentan aho-ra al reto de dotar a los títulos de mecanismos que aseguren la correcta formación y evaluación de este tipo de competencias presentes en el modelo enaee para ampliar el II TALLER DE INNOVACIÓN EDUCATIVA. COMPETENCIAS, FORMACIÓN Y EVALUACIÓNíndiceperíodo de concesión del sello. En la presente contribución se detalla el proceso que se ha seguido para idear, planificar y poner en marcha un procedimiento dirigido por los responsables de los títulos, y en el que han participado activamente los coordinadores de curso de los cuatro grados, para lograr el mencionado objetivo. El proceso, en fase de implementación, se pretende que esté implantado y verificada su eficacia, al menos de manera preliminar, en noviembre del 2018, fecha límite definida por aneca para dar cumplimiento a las prescripciones

Outcomes in Newly Diagnosed Atrial Fibrillation and History of Acute Coronary Syndromes: Insights from GARFIELD-AF

BACKGROUND: Many patients with atrial fibrillation have concomitant coronary artery disease with or without acute coronary syndromes and are in need of additional antithrombotic therapy. There are few data on the long-term clinical outcome of atrial fibrillation patients with a history of acute coronary syndrome. This is a 2-year study of atrial fibrillation patients with or without a history of acute coronary syndromes