Searched for: subject%3A%22Ceramics%22
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Simons, E.C. (author), Weerheijm, J. (author), Toussaint, G. (author), Sluys, L.J. (author)
In this study, the impact of a steel spherical projectile on an alumina ceramic is considered. New experimental and numerical results are presented and analysed. Numerical results are obtained using the Finite Element Method and the upgraded viscosity regularized Johnson-Holmquist-2 constitutive model to describe the ceramic material behaviour....
article 2020
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Tajdari, F. (author), Berkhoff, A.P. (author), van der Zee, R.A.R. (author), de Boer, A. (author)
article 2020
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Sherstoboeva, M.V. (author), Bavykina, A.V. (author), Bolgaru, K.A. (author), Maksimov, Y.M. (author), Sastre, F. (author), Skvortsova, L.N. (author)
Photocatalytic activity of metal-ceramic composites synthesized by self-propagating high-temperature synthesis (SHS) is investigated in the processes of degradation of diclofenac (DCF). Optical properties of the composites were studied, and the band gaps of ceramic matrix semiconducting components were calculated from the absorbance spectra. The...
article 2020
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Hafkamp, T. (author), van Baars, G. (author), de Jager, B. (author), Etman, P. (author)
Technical ceramic parts can be produced by curing ceramic-filled resins in the vat photopolymerization (stereolithography) process. Scaling up to larger ceramic product sizes and higher product quality calls for the integration of more sensing, actuation and closed-loop control solutions while taking a systems engineering approach. This paper...
conference paper 2020
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Pizzoccaro-Zilamy, M.A. (author), Huiskes, C. (author), Keim, E.G. (author), Sluijter, S.N. (author), van Veen, H. (author), Nijmeijer, A. (author), Winnubst, L. (author), Luiten-Olieman, M.W.J. (author)
Membranes consisting of uniform and vertically organized mesopores are promising systems for molecular filtration because of the possibility to combine high-flux and high-rejection properties. In this work, a new generation of mesoporous silica membranes (MSMs) have been developed, in which an organized mesoporous layer is directly formed on top...
article 2019
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Simons, E.C. (author), Weerheijm, J. (author), Sluys, L.J. (author)
Alumina ceramic is often used in armour systems. This material is known to have a brittle response under tensile loading, while a ductile response is found when sufficiently high pressures are reached. During projectile impact a ceramic material experiences both tensile loading and high pressures, hence fails in both a brittle and ductile way....
article 2019
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Carton, E.P. (author), Johnsen, B.B. (author), Rahbek, D.B. (author), Broos, J.P.F. (author), Snippe, A. (author)
The depth of penetration (DOP) method is a well-known ballistic test method for characterisation and ranking of ceramic armour materials. The ceramic tile is bonded to a backing material of semi-infinite thickness, and the penetration depth of the projectile gives a measure of the performance of the ceramic. There is, however, an inherent...
article 2019
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Hafkamp, T. (author), van Baars, G. (author), de Jager, B. (author), Etman, P. (author)
Vat photopolymerization is a prominent additive manufacturing technology for the fabrication of near-net shape ceramic parts. To serve the high tech industry’s needs, additive manufacturing equipment has to scale up to larger product sizes and higher, repeatable product quality. This motivates the integration of more process monitoring and...
article 2018
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Carton, E.P. (author), Roebroeks, G.H.J.J. (author), Weerheijm, J. (author), Diederen, A.M. (author)
Research on armor ceramics created only limited success in its search for relations between mechanical properties and the ballistic efficiency of this class of materials. Also TNO performed research on this subject using a range of experimental test set-ups (mainly using small and mid-caliber rounds) and diagnostic tools on a range of ceramic...
conference paper 2018
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Koivisto, A.J. (author), Kling, K.I. (author), Fonseca, A.S. (author), Brostrøm Bluhme, A. (author), Moreman, M. (author), Yu, M. (author), Costa, A.L. (author), Giovanni, B. (author), Ortelli, S. (author), Fransman, W. (author), Vogel, U. (author), Jensen, K.A. (author)
Nanoscale TiO2 (nTiO2) is manufactured in high volumes and is of potential concern in occupational health. Here, we measured workers exposure levels while ceramic honeycombs were dip coated with liquid photoactive nanoparticle suspension and dried with an air blade. The measured nTiO2 concentration levels were used to assess process specific...
article 2018
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Khanbareh, H. (author), de Boom, K. (author), van der Zwaag, S. (author), Groen, W.A. (author)
Tri-phase PZT-porous polyurethane (PU) composites are investigated with the aim of developing conformable, highly sensitive tactile sensors for application in Human-Machine Interactions. The main goal is to reduce the dielectric constant of the polymer matrix, and improve flexibility of traditional diphase piezo-composites, consisting of ceramic...
article 2017
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Khanbareh, H. (author), de Boom, K. (author), Schelen, B. (author), Scharff, R.B.N. (author), Wang, C.C.L. (author), van der Zwaag, S. (author), Groen, P. (author)
The need for flexible, highly sensitive tactile sensors that can fit onto curved surfaces is driving the conformable sensor materials research in the field of human–machine interactions. Here we report a new type of compliant piezoelectric active composite, a micro-porous polyurethane-PZT material, capable of generating a voltage output upon...
article 2017
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Deutz, D.B. (author), Mascarenhas, N.T. (author), Schelen, J.B.J. (author), de Leeuw, D.M. (author), van der Zwaag, S. (author), Groen, P. (author)
A highly sensitive, lead-free, and flexible piezoelectric touch sensor is reported based on composite films of alkaline niobate K0.485Na0.485Li0.03NbO3 (KNLN) powders aligned in a polydimethylsiloxane (PDMS) matrix. KNLN powder is fabricated by solid-state sintering and consists of microcubes. The particles are dispersed in uncured PDMS and...
article 2017
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Khanbareh, H. (author), Hegde, M. (author), Bijleveld, J.C. (author), van der Zwaag, S. (author), Groen, P. (author)
High temperature ferroelectrics for thermally stable devices that can detect pressure and temperature are of great industrial interest. Here we describe composites of lead titanate (PT) particle-polyetherimide (PEI) polymers with stable dielectric and piezoelectric properties over a broad range of temperature and frequency. The reported...
article 2017
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Shaji Karapuzha, A. (author), van der Zwaag, S. (author), Groen, W.A. (author)
Modern flexible and sensitive sensors based on polymer–ceramic composites employ lead zirconate titanate (PZT) granulates having the morphotropic phase boundary (MPB) composition as the piezo active ingredient, as this composition gives the best properties in fully ceramic piezoelectric sensors. In this study, the possibility of using PZT...
article 2016
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Deutz, D.B. (author), Mascarenhas, N.T. (author), van der Zwaag, S. (author), Groen, P. (author)
In this study, the influence of Li substitution on the piezoelectric performance of lead-free K0.5Na0.5NbO3 (KNN)-epoxy composites is explored. KNN piezoceramic particles modified with 0-12 mol% of Li are prepared via a double calcination technique, resulting in a perovskite particulate which transitions from an orthorhombic to tetragonal...
article 2016
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Zhao, D. (author), Katsouras, I. (author), Asadi, K. (author), Groen, W.A. (author), Blom, P.W.M. (author), de Leeuw, D.M. (author)
A homogeneous ferroelectric single crystal exhibits only two remanent polarization states that are stable over time, whereas intermediate, or unsaturated, polarization states are thermodynamically instable. Commonly used ferroelectric materials however, are inhomogeneous polycrystalline thin films or ceramics. To investigate the stability of...
article 2016
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Simons, E.C. (author), Weerheijm, J. (author), Sluys, L.J. (author)
The Johnson-Holmquist-2 ceramic model is used for quasi-static indentation simulation. A modification is proposed to an associated plasticity formulation. This allows for a fully implicit solution scheme, where dilatation is used instead of the traditional explicit bulking formulation. Dilatation is shown to have an important influence on ring...
conference paper 2016
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Carton, E.P. (author), Roebroeks, G.H.J.J. (author), Weerheijm, J. (author), Diederen, A.M. (author), Kwint, M.E. (author)
Several specially designed experimental techniques including an alternative test method have been developed for the evaluation of ceramic based armor. Armor grade ceramics and a range of combined materials have been tested using 7.62 AP rounds. Using the energy method [12] the dwell-time and total energy absorbed from the AP core were determined...
conference paper 2016
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van Dijk, R. (author), van der Bent, G. (author), Ashari, M. (author), McKay, M. (author)
We present a demonstration of an integrated circulator for TR modules using low temperature co-fired ceramic (LTCC) technology. Two different circulators have been realised to be used in TR modules in two different frequency bands, C-and Ku-band. The circulator is a three-port junction microstrip type device. The ferrite disc is embedded in the...
conference paper 2014
Searched for: subject%3A%22Ceramics%22
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