Fabrication of Nanostructured Metallized Glazes by Conventional Fast‐Firing Route

Abstract

A metallized glaze, suitable for large‐scale production, has been obtained starting from sepiolite‐n(Cu, Fe) as a stable vector containing the metal‐dispersed nanoparticles and following a conventional fast‐firing fabrication route. A small fraction of black carbon (about 4 wt%) was added to the starting mixture of the glaze to avoid oxidation of Cu nanoparticles in the 500°–700°C temperature range. At higher temperature (700°–1190°C), a fraction of the oxygen dissolved in the glassy phase is consumed by the Fe°/Fe2+ and Fe2+/Fe3+ redox reaction. Based on ellipsometric and quantitative optical reflectance measurements, it has been proven that the presence of a minimum concentration of Cu nanoparticles (∼10 vol%) in the top surface glaze layer is a prerequisite to obtain an appropriate metalize glaze.

Antibacterial and Antifungal Activity of ZnO Containing Glasses

“…However, as far as it is known, very few exploratory studies focused on complex phosphate glasses containing ZnO have been reported [ 26 , 27 ] and furthermore ZnO containing glasses have not been fabricated to be used as biocides, until now. Traditionally, ZnO has been a component in ceramic frites and glazes because of their excellent properties like chemical durability and mechanical stability [ 28 – 30 ]. These glasses have been employed for enameling because of their high refraction index, although they have been used less than the PbO glasses due to economic reasons.…”

Spectroellipsometric and ion beam analytical studies on a glazed ceramic object with metallic lustre decoration

“…Only one paper described spectroellipsometric study on nanostructured metallized glazes so far [5]. Those authors applied a double-layer optical model with Cu, CuO and SiO 2 components.…”

“…Pradell et al performed Rutherford backscattering spectroscopy (RBS) and optical measurements on laboratory prepared lusters and they have found that the high volume fraction of metal nanoparticles is responsible for the metallic shine [4]. Recently, a metallized glaze has been produced from sepiolite-n(Cu, Fe) containing metallic nanoparticles and applying a fast-firing fabrication process by Moya et al [5]. Based on ellipsometric and reflectance measurements, Moya et al draw the conclusion that copper nanoparticles in the topmost glaze layer is a prerequisite to obtain a metallized glaze.…”

Numerical Simulation of the Fast Firing of Alumina in a Box Furnace

“…The fastest heating rate possible to be obtained in conventional heating is accomplished by radiation, when a powder compact is introduced into a preheated intermittent furnace or into a sintering zone in a continuous furnace at sintering temperature. This procedure, known as fast firing, has been used in combination with short dwell time or even without it. During fast firing, an abnormally high densification rate was observed, producing a variety of dense materials with fine‐grained microstructures and properties comparable to those obtained using conventional firing schedules.…”