Technical ceramic
0.8-45 usd/kgTechnical ceramics, also called advanced ceramics, are a group of very hard, inert, and dimensionally stable oxides, carbides and nitrides. They are formed from powder, solid or gas, into engineering components and coatings used in some of the most demanding and extreme applications.
The chemical composition of these materials is carefully controlled and adjusted to suit the requirements of an application. 3D shapes are formed by pressing a powder into shape, CNC machining and sintering (fusing with heat). A range of processes exist for this, including those suitable for high volumes, such as die pressing (compacting into a mould) and ceramic injection moulding (a binder is added to the powder to help it flow into the mould under pressure). Isostatic pressing is used for smaller volumes. Powder is placed into a flexible mould (membrane) and pressure is applied by liquid or gas. With cold isostatic pressing (CIP), a second sintering step is required. In the case of hot isostatic pressing (HIP), the powder is sintered as it is formed, resulting in superior mechanical properties and surface finish.
With these processes it is possible to make parts with extremely precise dimensions and very thin wall sections. Applications span aerospace, architecture, military, industrial, automotive, electrical and medical applications.
As well as bulk 3D parts, technical ceramics are applied as coatings onto metal, glass and plastic by vacuum deposition. This technique is used by many industries – tooling, solar panels, medical, lighting, consumer products, jewellery and so on – to create thin film ceramic coatings for enhanced protection, performance and colour.
Sustainability concerns



Zirconium oxide (ZrO2), zirconia, has exceptional fracture toughness, higher than other technical ceramics. Its thermal coefficient of linear thermal expansion (CLTE) is very close to that of certain stainless, tool and alloy steels. This combination of properties make it ideal for use in items that are intimate with steel such as gears, bearings, plungers, piston rods and shafts. Zirconia is harder than steel, but not as hard or strong as other technical ceramics, and it is not suitable for use above 500 degC – even though its melting point is far higher, it is susceptible to cracking at high temperatures. This limits its use in high wear applications.
Other applications include jewellery, watches, medical implants, extrusion dies, rollers and valves. It has a fine grain, which enables an excellent surface finish – combined with its very high corrosion resistance and relatively high flexibility, this makes it suitable for use in kitchen knives and blades. The idea is they don’t need sharpening as much as steel. However, when they do, diamond polishing is required.