Known since the Stone Age, ceramics are now used in many advanced and technical applications due to their advantageous properties. Ceramics are no longer just tableware or tiles in your kitchen or bathroom. From pottery and building materials, to the most sophisticated implants, advanced ceramics are now indispensable materials in aeronautics, medicine, energy, environmental products and many other applications.
The standard ceramic production process – sintering – is rather simple: heating up a mixture of powders and salts at high temperature so that grains agglomerate and merge to form a compact mixed oxide, more or less porous. The control of this microstructure is complex but will lead to remarkable properties when mastered: porosity, hardness, resistance to high temperatures, chemical inertness and even lightness and transparency.
Let’s have a look through several examples of where these high-tech materials are used and how titanium dioxide (TiO2) – produced by Tronox for more than 100 years – can brilliantly broaden their potential.
Like diamonds, advanced ceramics are very hard, but they have a low toughness: They are not resistant to shocks and break easily. To remedy this, materials formed of a ceramic matrix reinforced by ceramic fibers have been developed. As a result, these ceramic matrix composites combine the strength and lightness of a composite with the high temperature resistance of ceramics. These materials are adapted to the most extreme conditions such as temperatures above 1000°C, thermal shocks, oxidizing and corrosive environments, and strong frictions. Potassium titanate (K2TiO3) ceramics made from anatase TiO2, such as Tronox’s TiONA® AT-1, ATP-01 and AT-1GG, are good examples of abrasion-resistant materials and are advantageously used in brake pads.
Porous by nature, ceramics can filter and purify liquids and gases. They are used in many applications, such as bacterial decontamination of water or pollution control of exhaust gases. The development of these filters requires engineering of the materials and, in particular, a deep control of the surface and porosity (sizes, connections, distributions of the pores). These two parameters will define the selectivity of the filter regarding the targeted species. Our Tronox Ultrafine CristalACTiV™ DT series grades are particularly suited for this application. As another example, Tronox Specialty TiO2 is used to manufacture aluminum titanate (Al2TiO5) based filters to retain particulates from the exhaust gas of internal combustion engines.
Among other mixed oxides made from TiO2, we can also mention potassium titanyl phosphate (KTiOPO4), a non-linear optical material used in lasers or strontium titanate (SrTiO3), a transparent ceramic material, as an excellent diamond substitute. Talking about electroceramics, TiO2 is a key component, e.g. for the production of barium titanate (BaTiO3) and calcium copper titanate (CaCu3Ti4O12) used in multi-layer capacitors; for making lead zirconium titanate (Pb[Zrx, Ti1-x]O3) used as piezoelectric materials, or for the synthesis of bismuth titanate (Bi12TiO20) as an electro-optical transparent ceramic. Our newly developed CristalACTiV™ High Purity Ultrafine grades (HPX) are perfectly suited for these applications.
Tronox has been in the specialty TiO2 market for more than 30 years with stable and consistent production and with integrated ore supply. Our extensive TiONA® and CristalACTiV™ portfolio offers a wide range of solutions. Visit us at www.cristalactiv.com to learn more about Tronox’s ultrafine and specialty TiO2 grades.
Cristal, now as part of Tronox, is continuously developing new CristalACTiV™ materials to meet existing and future environmental regulations and respond to the needs of innovative applications.