Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5437722 | Ceramics International | 2017 | 40 Pages |
Abstract
Hematite is responsible of the reddish hue of ceramics and its nucleation is strictly related to firing temperature and chemical composition of the raw materials. A low CaO concentration allowed hematite to form in higher amounts providing a more intense reddish hue at high firing temperatures (over 950 °C). At the highest temperature (1100 °C) all samples showed darker colour due to increased size of iron oxide particles. Black core developed in Ca-rich ceramics fired at low temperatures as the short time of firing is insufficient to complete iron oxidation within the matrix, except in those containing high temper amounts. Indeed, microstructural modification occurs due to the presence of discontinuities among temper grains and matrix, which improves the circulation of oxygen in the core of ceramics.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Alberto De Bonis, Giuseppe Cultrone, Celestino Grifa, Alessio Langella, Antonio P. Leone, Mariano Mercurio, Vincenzo Morra,