Zirconia

Zirconia - an extremely resistant material

Zirconia or zirconium dioxide as it is also called—is a synthetic mineral derived from zircon sand, found in sedimentary deposits of heavy mineral sand, formed as the result of the alteration of granitic or alkaline rocks. 

Fused zirconia is produced from the carbothermal reduction of zircon sand which is heated in an electric arc furnace at temperatures exceeding 2,600°C. Once cooled, the resulting coarse granular material is crushed and sized to meet the required specifications.

Chemical zirconia is produced through the chemical reaction of caustic soda with zircon sand, followed by various chemical processes. 

Zirconia is a very hard material with an extremely high melting point. It is chemically stable at high temperatures, oxide ion-conductive and abrasion and corrosion-resistant. These properties make it highly valuable in a broad range of industries such as refractories, investment casting, advanced ceramics, fuel cells, dental ceramics, brake pads, catalytic convertors, and, in its cubic, polished form, as an inexpensive alternative to diamonds.

Physical properties

• Very high melting point
• Chemical stability at high temperatures
• Low thermal expansion compared to metals
• High mechanical resistance
• Hardness (8 – 8.5 on Mohs scale)
• Abrasion resistance
• Corrosion resistance
• Oxide ion conductivity (when stabilized)
• Chemical inertia

Imerys - world #1 producer of fused zirconia

Imerys produces high-quality fused zirconia and zirconium chemicals at state-of-the-art processing facilities in the USA, Germany and China serving an industrial client base worldwide. Zircon sand is sourced outside the Group. 

Upstream, our S&T teams at our Technology Center in Villach Austria conduct extensive applications development and research into high resistance materials such as zirconium oxide.

Zirconia - an ultra-robust mineral for refractories and metallurgy

In refractory applications, Imerys fused zirconia powders are prized for their high-temperature resistance and low thermal expansion. They are used in refractory parts in the continuous casting of steel; as binders in furnace linings; in kiln furniture for glass and aluminum manufacturing; in crucibles; and in filters for foundry steel casting. 

In the production of zirconium and hafnium metals, Imerys high-purity, monoclinic zirconia products help lower waste material rates and boost yields.

Used in advanced ceramics, brake pads aerospace coatings, and many others 

Owing to their crystalline structure and mechanical strength, Imerys fine-grade zirconia powders are the main constituents of advanced ceramic components for the manufacture of oxygen sensors, automotive components, cutting tools, ceramic filters, tools and dies, pump, valve components and assay crucibles.

Our advanced ceramic yttria stabilized zirconia are key components for providing ionic conductivity in energy converters such as Solid Oxide Fuel Cells (SOFC) and Solid Oxide Electrolysis Cells (SOEC).

Imerys zirconia powders and zirconium chemicals are used for various catalytic reactions, such as emissions control in automotive applications and the chemical industry.

In friction applications such as Non-Asbestos Organic or NAO brake materials, our Zirconia powders can reduce pad and rotor wear while assisting in the effectiveness of the transfer film overall enhancing NVH benefits (noise, vibration and harshness).

Used as high-temperature thermal plasma spray coatings in aero-engine and gas turbines, Imerys zirconia powders are valued for their high melting point, low thermal conductivity and excellent corrosion and wear resistance. 

Imerys zirconium chemicals such as zirconium oxychloride (ZOC), zirconium basic carbonate (ZBC), zirconium basic sulphate (ZBS), zirconium ortho sulphate (ZOS) are also key components in a variety of consumer goods such as paints, inks, paper, antiperspirants and water-proof textiles—to name a few.

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With a solid industrial footprint on three continents to serve customers worldwide, Imerys is in a strong position to meet the growing demand for value-added, zirconia-based speciality products and solutions.