The high temperature ceramic is the key to modern science due to the versatile applications they are subjected to. The properties of these ceramic such as mechanical strength, temperature resistance and thriving under harsh conditions benefits each process. This article explores some of the best high temperature ceramics present globally.

Define Heat resistance? Is Ceramic heat Resistant?

Heat resistance plays a significant role in Ceramic material properties. Heat resistance meaning is simple, it is the ability of a material to oppose heat current passing through them. Ranging from traditional to technical ceramic, ceramics are known for their ability to withstand high temperature.

Ceramics are heat resistant; the high temperature Ceramic is meant to work at operating temperature around 2000 degC. The top 10 ceramic materials with higher operating temperatures are given below.

1. Tungsten Carbide: Operating temperature 3000 degC

Tungsten carbide known for its extreme hardness is a high temperature ceramic often used in heavy servicing applications. Tungsten carbide ceramic material is challenging as it tends to be brittle in certain servicing applications.

Properties of Zirconia Toughened Alumina (ZTA)

• They possess superior impact resistance and are hard, rigid and resist deformation

• Good dimensional stability

Applications

• Used in high-speed cutting material and carbide grade wear resistant material.

2. Magnesia: Operating temperature 2800 degC

Magnesia works at the highest temperature range as a high temperature ceramic. They are ideal for insulation at high temperature and offers excellent shock resistance

Properties of Zirconia Toughened Alumina (ZTA)

• Chemically inert, Excellent wear resistance and good fracture toughness ceramic material  

• They possess increased tolerance to hydrothermal ageing

Applications

• Rollers, Metal dies, threads and wires

• Employed in high pressure process Equipments

3. Boron Nitride: Operating temperature 2000 degC

Boron Nitride is a high temperature ceramic which is available both in powder and solid form. BN is present in different ceramic structures such as Pyrolytic Boron Nitride (P-BN) and hexagonal boron Nitride (H- BN).

Properties of Boron Nitride

• Extreme thermal shock resistance

• Low density and high thermal conductivity

• Chemically inert and resists corrosion

• High dielectric breaks down strength is greater than > 40 KV/mm

Applications of Boron Nitride

• Used in Heat resistant valves, lubricants and fixtures

• Used as a Refractory ceramic material 

• Deployed as Plasma chamber ceramic components, vacuum furnace supports and feedthrough

• Used as Casts for molten metal, glasses and spaces for high temperature applications

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4. Aluminum Nitride: Operating temperature 1900 degC

Aluminum Nitride is a kind of ceramic that is similar to Beryllium oxide in application. AlN is known for their better electrical insulation properties and higher thermal conductivity. Since the coefficient of expansion of this high temperature ceramic matches silicone, it is often used as substrates and PCB material.

Properties of Aluminum Nitride

• AlN have conductance almost 5 times of that of Alumina

• Helps in proper heat dissipation and fast functioning of high-performance material

• Aluminum Nitride holds extreme shock resistance

Applications of Aluminum Nitride

• Used as electronic insulators in high power applications

• Used as heat sink and dissipation ceramic elements in power electronics

• Optoelectronic ceramic components and substrate material

5. Silicon Carbide: Operating temperature 1900 degC

Silicon carbide is one among the lightest and hardest material in ceramics that has higher thermal conductivity. They have thermal coefficient of expansion low and are generally resistant to acids.  They are resistant to any erosion or wear and tear in harsh atmospheric conditions.

Properties of Silicon Carbide

• They are extremely hard in nature

• Silicon carbide has greater wear and tear resistance. The corrosion resistance of the ceramic component is on higher side.

• They have higher thermal conductivity, lower thermal expansion coefficient and higher young’s modulus

Applications of Silicon Carbide high temperature ceramic

• Industrial components such as exchangers, Blast furnace material, Burners and valve parts

• They are used as Kiln ceramic parts

6. Alumina (Al2O3): Operating temperature 1750 degC

Alumina is the most common ceramic material with higher thermal stability, mechanical strength and purity value of 99.9%.  They offer higher electrical insulation properties and is resistant to both acids and alkalis.

Properties of Alumina

• High hardness and mechanical strength

• They are known for superior Wear and abrasion resistance

• Alumina has high compressive and dielectric strength.

Applications

• Electrical insulators at high temperature

• Laser Tube and other components

• Machine components, bearing material and semiconductor parts

• Valve seats, Wire and thread materials and Armor materials.

7. Boron Carbide (B4C): Operating temperature 1800 degC

Boron Carbide, the high temperature ceramic has a thermal stability at around 1800 degC. They are extremely light weight and stands next to diamond. The higher mechanical strength and wear resistance makes them an ideal fit for higher stress applications.

Properties of Boron Carbide

• High hardness and melting point

• Low density of material

• Superior thermos -electrical properties and excellent absorption of neutrons in cross section.

Applications

• They are used in defense as armors, function as gun nozzles and are used as bulletproof tiles.

• In nuclear reaction engineering, they are used as control rods and provides shielding from radiation and neutrons

• Boron carbide is used as cutting tools and wear and abrasion resistant parts for components

8. Silicon Nitride (Si3N4): Operating temperature 1400 degC

Silicon Nitride is a high temperature ceramic that is quite known for its thermal and impact resistance. It is suitable for high temperature and high load applications.

Properties of Silicon Nitride

• High fracture toughness and flexural strength

• Low thermal expansion

• Good oxidation resistance and work well as electrical insulators

• Thermal shock resistance and works well at higher temperature

Applications

• Aerospace and Engine applications such as seal elements, valves, rotors

• Medical applications or biomedical implants

• Mechanical or industrial applications

• Crucible material and cutting tools due to their extreme hardness

9. Zirconia (ZrO2): Operating temperature 1500 degC

Zirconia is a highly durable high temperature ceramic with good thermal shock resistance and excellent mechanical strength. Zirconia ceramic material is available in different grades including partially stabilized Zirconia or Yttrium stabilized Zirconia. However, the operating context is very crucial to determine the usage of different grades of Zirconia

Properties of Zirconia

• Applicable up to a temperature of 1000 degC

• Chemically inert and resultant to molten metals

• High fracture toughness and hardness

Applications

• Used for the manufacture of high-density grinding media

• Used for mechanical components such as ball valve seats and balls

• Refractory ceramic for high temperature induction furnace or any other heating system.

10. Zirconia Toughened Alumina (Zr – AL2O3): Operating Temperature 1500 degC

Zirconia toughened Alumina is a ceramic composite made with high precision exhibiting properties of both Alumina and Zirconia

Properties of Zirconia Toughened Alumina (ZTA)

• Chemically inert, Excellent wear resistance and good fracture toughness ceramic material  

• They possess increased tolerance to hydrothermal ageing

Applications

• Rollers, Metal dies, threads and wires

• Employed in high pressure process Equipments

Bottom Line

The information on the top 10 high temperature ceramic has been covered in the article with temperature ranges and properties mentioned. However, context of usage is prime before subjecting the high temperature ceramic into applications. Of the ceramics available, Tungsten carbide tops in terms of temperature resistance followed by ZTA.