RESEARCH Development of temmoku glazes and their applications onto different tiles under industrial fast firing conditions at 1180 °C Keriman Pekkan 1 & Eda Taşçı 2 & Yalçın Gün 3 Received: 17 April 2018 /Revised: 7 February 2019 /Accepted: 5 May 2019 # Australian Ceramic Society 2019 Abstract Temmoku glazes are special and artistic glazes that are used in certain applications. Temmokus are either slip glazes made from ferruginous clay or feldspathic type glazes containing iron oxide. Glaze composition, clay body, application method, and firing regime are the most important factors for achieving these kinds of glazes. In this study, a new temmoku glaze composition was developed and applied on floor and porcelain tile bodies, respectively. Industrial fast firing processes were conducted at Altın Seramik Factory at 1185 °C. All of the glaze surfaces were smooth and glossy after industrial fast firing. Color of the glazes was black metallic with an oil spot effect. L*a*b* values were measured by a spectrophotometer. Final surfaces of the temmoku glazes were visualized by polarized optical microscope and characterized by an X-ray diffractometer (XRD), scanning electron microscopy (SEM), and energy dispersive x-ray (EDX). Generally, temmoku glazes displayed lower L* values on both floor tile and porcelain bodies. According to the compositional modifications, adjusting the SiO 2 /Al 2 O 3 ratio was critical and the maxi- mum Fe 2 O 3 content should not exceed 5%. This study showed that various visual effects are related with different crystal morphology of quartz, magnetite, maghemite, and hematite and that the microstructure has an important effect on color and appearance of temmoku glazes. Keywords Temmoku glaze . Porcelain body . Industrial firing . Glaze characterization Introduction The glaze applied on ceramic substrate is a thin glassy layer formed by combining vitrifying oxide and inorganic additives at certain ratios [1]. The properties such as adhesion to sub- strate, decorative and esthetic surface, texture, resistance to chemical attack, mechanical strength, and compatibility of thermal expansion are determined by chemical composition of the glaze [2–4]. Color diversity, brightness, transparency, whiteness, and opaqueness are glaze-related esthetic charac- teristics that provide an attractive appearance for the clay body [5]. Ceramic glazes can be classified as leaded, non-leaded, raw, or fritted depending on their composition or type of pro- duction or, as high- or low-viscous glazes by making a gener- alization that can cover all of these groups. In addition, glazes can also be classified according to some criteria such as sin- gle-firing, double-firing, and different firing atmospheres [4, 6]. Today, in order to increase product diversity and competi- tion, there are studies carried out on glazes with artistic surface appearance equivalent to these types of glazes, and on glazes with technical characteristics suitable for industrial production [7–9]. Single step heat treatment is necessary for the fast firing technology. In order to develop a glaze composition suitable for industrial production, the desired maturation and devitrifi- cation processes should occur in a limited temperature interval during the firing cycle. The most important technical charac- teristic of the glaze is the chemical composition. The designed glaze formula should be adaptable to the applied body and furnace heat treatment cycle. Moreover, the final crystal phases should be stable and no phase transformation should *Some part of this study was presented as a poster in the 5 th Mediterranean Clay Meeting in Izmir, Turkey, in September 2016 and the copyright for those parts belongs to MCM201625. * Keriman Pekkan keriman.pekkan@dpu.edu.tr 1 Faculty of Fine Arts, Department of Ceramic and Glass, Kutahya Dumlupinar University, Kutahya, Turkey 2 Department of Metallurgical and Materials Science and Engineering, Kutahya Dumlupinar University, Kutahya, Turkey 3 Graduate School of Natural and Applied Sciences, Kutahya Dumlupinar University, Kutahya, Turkey Journal of the Australian Ceramic Society https://doi.org/10.1007/s41779-019-00357-z