6 Properties To Consider When Specifying Refractory Materials
Choosing a refractory material involves much more than identifying the highest temperature it can withstand.
Different industrial processes expose refractory components to very different combinations of heat, thermal cycling, chemical attack, abrasion and mechanical stress. As a result, engineers and specifiers need to consider the complete operating environment when determining the material requirements for an application.
Here are six important refractory material properties that can influence performance.
1. Maximum Service Temperature
Temperature is one of the most fundamental considerations when specifying refractory materials.
Different refractory materials are designed to operate within different temperature ranges, so the specified material must be capable of maintaining its required properties under the expected operating conditions.
However, maximum temperature is best considered alongside other factors. How frequently temperatures change and the other conditions the component encounters can be equally important.
2. Thermal Conductivity
Thermal conductivity determines how readily heat passes through a material.
In some applications, low thermal conductivity is required to minimise heat loss and provide effective insulation. In others, efficient heat transfer is an important part of the process.
This is why different refractory materials can perform very different roles within high-temperature equipment.
3. Thermal Shock Resistance
Industrial processes don’t always operate at a constant temperature.
Repeated heating and cooling can place significant stress on refractory components as materials expand and contract.
Where frequent or rapid temperature changes are expected, thermal shock resistance can therefore be an important part of the refractory specification.
4. Chemical Resistance
Refractory components may come into contact with molten metals, slags, gases, glass or other chemically aggressive substances.
The chemical environment can have a significant impact on refractory performance, making compatibility between the specified material and the substances it will encounter an important consideration.
Materials including silicon carbide and zirconia can provide valuable properties for demanding applications where chemical resistance is required.
5. Mechanical Strength
Refractories don’t only have to withstand heat.
Depending on the application, components may also experience mechanical loads, impact or other physical stresses throughout their service life.
The required mechanical properties will therefore depend heavily on where and how the refractory component is used.
6. Abrasion and Wear Resistance
Movement of materials, particles and process media can gradually wear refractory surfaces.
For applications exposed to significant abrasion, the refractory specification may need to prioritise wear resistance alongside thermal and chemical performance.
Selecting materials with appropriate properties for these conditions can help support reliable performance throughout the component’s intended service life.
Refractory Material Specifications Depend on the Application
There is no single refractory material that provides the ideal combination of properties for every high-temperature process.
Operating temperature, thermal conductivity, thermal cycling, chemical exposure, mechanical loading and abrasion all need to be considered as part of the specification.
At Vulcan Refractories, we manufacture refractory products to customer specification, using a range of proven material formulations, including silicon carbide, zirconia and zircon-based materials, high-alumina insulating refractories and hybrid mullite-silicon carbide materials.
From standard products to bespoke shapes, our UK manufacturing capabilities allow us to produce refractory components that meet the requirements specified by our customers.
Looking for refractory components manufactured to your specification? Contact Vulcan Refractories to discuss your requirements.