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Alumina Ceramics – Mechanical Strength, Hardness and Thermal Stability

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Alumina Ceramics – Mechanical Strength, Hardness and Thermal Stability

Alumina ceramics boast superior mechanical strength and hardness as well as thermal stability due to their dense crystal structure. Manufacturing techniques used for the production of metal parts include dry pressing, isostatic pressing and injection molding. After molding is completed, the formed powder must be densified through sintering at high temperatures in order to induce particle rearrangement, grain growth and pore elimination.


Alumina (Al2O3) is an industrial ceramic with exceptional mechanical strength and wear resistance. Additionally, it’s resistant to chemical attack at both room temperatures and higher ones.

Alumina is produced from bauxite, an aluminum-rich clay like material mined from the earth and processed through grinding into white powder form. Alumina finds widespread industrial uses due to its excellent wear, corrosion and chemical resistance as well as thermal stability and low expansion properties. Furthermore, alumina’s hardness (second only to diamond on the Rockwell scale) withstands bullet impacts making it suitable as body armor.

Hardness makes Alumina difficult to machine, yet can still be achieved using special tooling. Alumina’s abrasion resistance surpasses that of most metallic materials including stainless steel and tungsten carbide tools; additionally it is chemically inert protecting it against acids or alkalis at high temperature.

Alumina can be formed into complex shapes using dry pressing, isostatic forming, tape casting, injection and compression molding techniques to achieve high dimensional accuracy and surface finish. When combined with zirconia it forms CeramAlloy ZTA which retains all the advantages of hard alumina while offering increased fracture toughness and bending strength thanks to zirconia’s superior fracture toughness properties.

Thermal Stability

Thermal stability refers to a technical ceramic’s ability to function consistently and reliably across a wide temperature range. Alumina ceramics demonstrate high thermal resistance with minimal temperature expansion rates – ideal for applications requiring precision and consistency.

Alumina is inert, which makes it resistant to chemical corrosion from acids and alkalis at high temperatures, and features excellent wear resistance which allows it to retain its shape even under constant friction or mechanical strain.

Due to its excellent properties, alumina has long been used in ballistics applications as it can withstand initial impact of bullets without breaking apart under their force. Alumina can also protect bodies of guns, missiles and helicopters against projectile penetration by serving as bullet-resistant shielding material.

International Syalons’ Durox brand of alumina ceramics come in various shapes, sizes and purities to meet specific advanced ceramic needs. Commonly found in electronic manufacturing for quick heat dissipation. Durox ceramics also boast excellent dimensional stability and low thermal expansion which maintain tolerances across a range of temperatures. If you would like to learn more about our complete selection of Al2O3 technical ceramics – get in touch today – our team is on standby ready to assist in finding you a solution for your next engineering project.

Resistance to Corrosion

Chemical resistance of an alumina ceramic depends on its purity and microstructure, as well as on factors like aggressive media type and ambient temperature. This is particularly pertinent to alumina ceramic used in oil and gas industries which expose them to harsh chemicals at elevated temperatures.

Resistance of Alumina Ceramics to Corrosion provides many applications with significant advantages. This is particularly the case for parts designed to resist impingement damage caused by turbulent or impinging flow conditions, where these types of ceramics provide significant resistance against impingement damage caused by impinging flow or turbulent turbulence. Furthermore, their hard and non-oxidizing properties reduce equipment failure caused by cavitation and oxidation processes.

Alumina ceramics have long been utilized as crucial components in chemical processing environments, being exposed to highly acidic and concentrated solutions. Their strong corrosion-resistance allows these parts to withstand these extreme environments for extended system lifetime.

Corrosion resistance of alumina ceramics can be further increased through the incorporation of various additives. Manganese oxide (MnO2) can enhance hardness and thermal shock resistance; silicon dioxide (SiO2) increases corrosion resistance while decreasing porosity; while zirconium oxide (ZrO2) boosts both thermal shock resistance and wear resistance – tailoring both additives used and their respective chemistry to meet specific application requirements is possible.

Electrical Conductivity

Alumina’s chemical stability is one of the primary reasons it is used in ceramic manufacturing. Alumina does not react with silica, tin, chromium, manganese, iron, titanium, zirconium or any other metals used during melting of pure metals and glass. Furthermore, alumina resists erosion caused by melting steel slag; additionally it stands up well to erosion from erosion caused by melting steel slag; furthermore its resistance to corrosion and erosion make alumina ideal for use as refractory material furnace tubes or drawing crucibles – acids such as sulfuric hydrochloric and nitric acids have no adverse reaction against it either!

Alumina ceramic has an extremely low dielectric loss – energy lost when electric current passes through it – which makes it an excellent insulator and prevents electron flow through. This material is second only to diamond on the Mohs scale of hardness and used for making industrial wear-resistant materials and components for many different applications. Alumina can be used to fabricate pressure sensors for fluid flows and welding nozzles as well as insulators for these purposes. Furthermore, its properties also make it suitable for use as component feedthroughs for X-ray component feedthroughs or high voltage bushings. Other forms of alumina are used as counter face seals on pumps that handle chemicals and nuclear grade insulator components, as well as ceramic-to-metal seals due to its lower temperature coefficient of expansion than other metals; this ensures long-term reliability and integrity even under harsh environmental conditions.

alumina ceramics