Objective
The low fracture resistance of the green bodies used in ceramic tile manufacture produces broken corners, cracking and tile failure in the prefiring stages, and represents one of the main sources of flawed tile. Although these defects originate in the green tile body, a part of these remains undetected until the tile has been fired, which is precisely when it reaches its highest added or commercial value. Currently around 3% of unfired glazed tile is scrapped. Although this scrap is reused in the same manufacturing process, it represents a significant cost, as the unfired glaze layer cannot be reused. On the other hand, about 2% of fired tile is scrapped, involving an important production loss and environmental impact owing to the difficulty of reusing this scrap in the tile manufacturing process. The economic losses stemming from this scrap in total EU ceramic tile production can be assessed at over 175 million ECU, generating around 500,000 t of fired tile waste, of which 50% is reused in the tile manufacturing process, while the remainder needs to be disposed of or recycled in other industrial processes. This project is intended to improve the mechanical properties of green bodies with a view to reducing the economic cost and environmental impact caused by the above economic losses and waste. The fracture mechanism of green ceramic bodies will therefore be studied, defining which mechanical properties of these bodies (mechanical strength, modulus of elasticity and toughness) limit the appearance of the above defects in each process stage (pressing, drying, glazing and firing), establishing methods for the industrial measurement and control of these properties. The relationship will also be determined between process variables, pressing powder characteristics, composition of the raw materials mixture, and presence or absence of additives on the foregoing properties, so as to optimise the processes and produce more robust materials. A consortium has been formed to carry out the project, consisting of three R+TD Centres from different European Union Member States (Italy, United Kingdom and Spain), which have been actively engaged for many years as R+TD performers in the ceramic tile manufacturing branch in their respective countries, and nine companies from these same countries, involving manufacturers of different types of ceramic tiles, and clay, spray dried powder, and additives suppliers. Project timing has been set for two years.
Fields of science
Not validated
Not validated
Topic(s)
Call for proposal
Data not availableFunding Scheme
CRS - Cooperative research contractsCoordinator
12200 Onda
Spain