Monolithic Ceria-stabilized Zirconia (CeTZP) is a material that is suitable for use at higher temperatures and in highly aggressive and corrosive environments. UltraHard Materials USA LLC (UHM) is a producer of precision components made from CeTZP engineering ceramic.
Unlike conventionally-produced CeTZP engineering ceramic, UHM's CeTZP ceramic, we believe, has the best combination of high hardness, high toughness, high bend strength and high compression strength as well as better environmental stability making it, we reckon, the best candidate material among all of the commercial monolithic engineering ceramics currently available for wear-resistant applications under load-bearing conditions.
Need for Ceramics
Engineering systems and products are becoming increasingly sophisticated. They are required to perform more complex tasks than ever before as well as perform under increasingly severe operational conditions. Such high performance systems and products are demanding more of the materials from which they are being made.
Engineering ceramics are ideally suited for such high performance applications where a combination of properties such as wear resistance, hardness, stiffness and corrosion resistance are important. In addition to these properties, engineering ceramics have relatively high mechanical strength at high temperatures.
Ceramics or Metals
The direct substitution of a metal component for its ceramic counterpart is often not a simple, straightforward and viable approach*. It can, for instance, have a detrimental "knock-on" effect on adjacent metal components. Direct substitution problems include differential wear rates, contact stresses at interfaces, stress rupture life, thermal shock resistance and thermal expansion mismatch.
In some cases, the benefits of substitution outweigh the disadvantages of the "knock-on" effect. In other cases it is important to design, from the "ground up", a new product using ceramic components utilizing the exceptional properties of engineering ceramics. This approach could also be prudent and beneficial because the design criteria for ceramics are different to those of metals.
* M. van Roods, M.K. Ferber, and D.W. Richerson (Editors) 2002 "Ceramic Gas Turbine Design and Test Experience" American Society of Mechanical Engineers Press (USA).
Why Use CeTZP Ceramic?
Monolithic CeTZP engineering ceramic possesses three properties suitable for internal combustion engines and turbine engines - high temperature capability, low thermal conductivity and corrosion-resistance:
(1) a CeTZP ceramic engine can operate at higher temperatures (> 800 C) resulting in higher combustion efficiencies, and
(2) a CeTZP ceramic engine can be more thermally efficient. Less heat would be lost to its surroundings because of its low thermal conductivity (~2 W/m.K).
(3) CeTZP ceramic does not usually undergo hydrothermal degradation especially in the humid corrosive environment of an IC engine or a turbine engine.
More About UHM's CeTZP
When compared to other engineering ceramics, such as silicon nitride, silicon carbide and alumina, the zirconia family of ceramics offer a combination of properties that make them attractive candidate materials. Most notable are their higher fracture toughness and their corrosion and chemical resistance.