More about Refractories

Click here to find Refractories Manufacturers | Discuss Refractories & Other Topics

Refractory materials are substances with extremely high melting points that can withstand high temperatures without losing strength. Typically, refractory materials are produced from lime (calcium oxide) or magnesium oxide, and are used for a number of high temperature applications. These applications include furnace linings, thermal barriers, heat containment in testing facilities, incinerator parts and crucibles. Other materials are also used as refractories, such as hafnium, iridium, molybdenum, tantalum and tungsten based substances; silicon carbide; zircon; and fireclay.

Key among the properties necessary for effective function as a refractory material are exceptional resistance to thermal shock, resistance to softening and chemical instability, minimal thermal conductivity and high strength. Depending on the application, manufacturers can select refractories from a wide range of shapes, thicknesses and designs. They are produced in brick, mortar, board, sheet and tile form, as well as in an extensive variety of custom shapes. A number of manufacturers also offer standard and custom refractory installation services for new or refitted heating facilities.

Choice of the proper refractory material depends on the nature of the application, as some refractories will have undesired results when used in certain conditions. Typically, acidic and basic refractories can only be used for like applications (acid with acid, base with base). Additionally, there are a very wide number of materials considered as refractories (more than five thousand), many of which are not suitable for certain temperatures and environments. In some cases, a primary aspect of the desired material is to withstand slag erosion and regular contact with molten metal, while in others it is the ability to function in oxygen-rich areas. Although not suitable for all high-temperature applications due to concerns over the conditions of the operation, all refractories typically exhibit resistance to temperatures over one thousand degrees Fahrenheit. They can regularly be categorized as either fired shapes or monolithic refractories.