Assessment of some locally produced Egyptian ceramic wall tiles

Due to the fact that there are various types of wall tiles in the Egyptian market, of different qualities and prices, the aim of this research paper is to evaluate the properties and characteristics of tiles obtained from the local Egyptian market and attempt to identify the reasons for such differences. In other words, investigate the reasons why some tiles are more superior in quality than others. Test specimens were obtained from the local Egyptian market for fourteen factories. The mechanical properties (namely flexural strength) and physical properties (namely water absorption and apparent porosity) were measured, as they reflect the strength, the endurance during handling, as well as, the conditions to which the tiles are expected to be exposed to during use. The impact resistance and hardness were tested as well. Also, the phases (both major and minor) developed during the firing (maturing) step of manufacturing were identified. A correlation was made between the measured properties and the formed phases. The results showed that samples which yielded high physical and mechanical properties are those that constituted mainly the major phases, specifically, mullite and quartz, while those that contained impurities in the raw materials inevitably resulted in the development of minor phases, in addition to the major phases, had a negative effect on the measured properties. Consequently, it is feasible to obtain tiles that satisfy the requirements of ISO 13006 specification provided that the used raw materials are free (as much as possible) from impurities such as hematite, magnesium, and calcium.