Kiln furniture are devices and implements inside furnaces used during the heating of manufactured individual pieces, such as

pottery Pottery is the process and the products of forming vessels and other objects with clay and other ceramic materials, which are fired at high temperatures to give them a hard and durable form. Major types include earthenware, stoneware and por ...

or other ceramic or metal components.Kiln Furniture
Fraunhofer Institute of Silicate Research Kiln furniture is made of

refractory material In materials science, a refractory material or refractory is a material that is resistant to decomposition by heat, pressure, or chemical attack, and retains strength and form at high temperatures. Refractories are polycrystalline, polyphase, ...

s, i.e., materials that withstand high temperatures without deformation.G. Bickley Remmey, ''Firing Ceramics'', , 1994
Section 4. Kiln Furniture
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Materials

Commonly used materials are

cordierite Cordierite (mineralogy) or iolite (gemology) is a magnesium iron aluminium cyclosilicate. Iron is almost always present and a solid solution exists between Mg-rich cordierite and Fe-rich sekaninaite with a series formula: to . A high-temperat ...

(up to 1275 °C),

mullite Mullite or porcelainite is a rare silicate mineral formed during contact metamorphism of clay minerals. It can form two stoichiometric forms: 3 Al2 O32 SiO2 or 2Al2O3 SiO2. Unusually, mullite has no charge-balancing cations present. As a result, th ...

(up to 1750 °C),

silicon carbide Silicon carbide (SiC), also known as carborundum (), is a hard chemical compound containing silicon and carbon. A semiconductor, it occurs in nature as the extremely rare mineral moissanite, but has been mass-produced as a powder and crystal sin ...

(up to 1500 °C), alumina (up to 1750 °C),

zirconia Zirconium dioxide (), sometimes known as zirconia (not to be confused with zircon), is a white crystalline oxide of zirconium. Its most naturally occurring form, with a monoclinic crystalline structure, is the mineral baddeleyite. A dopant sta ...

(up to 1650 °C). The choice depends on cost, weight, and physical properties.

Functions and effects

Functions of kiln furniture include carrying the

kiln A kiln is a thermally insulated chamber, a type of oven, that produces temperatures sufficient to complete some process, such as hardening, drying, or chemical changes. Kilns have been used for millennia to turn objects made from clay int ...

furnace A furnace is a structure in which heat is produced with the help of combustion. Furnace may also refer to: Appliances Buildings * Furnace (central heating): a furnace , or a heater or boiler , used to generate heat for buildings * Boiler, used t ...

load and protecting the load from various kind of damage: open file, smoke, debris, from deforming or sticking the components to each other. In addition to various carriers and plates, capsules with heating material may be used. Kiln furniture influences the heat distribution in the furnace and the interaction of the load with the atmosphere in the furnace. Since the furniture is being heated along with the load, this increases energy consumption hence the operating costs increase. An additional increase of costs comes from wear of the furniture due to thermomechanical and chemical stresses. To decrease heat capacity porous materials or thinner furniture components may be used. However this calls for a trade-off with load-bearing capacity and stress resistance.

Types of kiln furniture

saggar A saggar (also misspelled as sagger or segger) is a type of kiln furniture. It is a ceramic boxlike container used in the firing of pottery to enclose or protect ware being fired inside a kiln. Traditionally, saggars were made primarily from ...

(also misspelled as sagger or segger) is a ceramic boxlike container used in the firing of

to enclose or protect ware being fired inside a

. Saggars have been used to protect, or safeguard, ware from open flame, smoke, gases and kiln debris. Traditionally, saggars were made primarily from

fireclay Fire clay is a range of refractory clays used in the manufacture of ceramics, especially fire brick. The United States Environmental Protection Agency defines fire clay very generally as a "mineral aggregate composed of hydrous silicates of alumin ...

. Modern saggars are made of alumina ceramic,

ceramic,

ceramic

and in special cases from

A pernette or

stilt Stilt is a common name for several species of birds in the family Recurvirostridae, which also includes those known as avocets. They are found in brackish or saline wetlands in warm or hot climates. They have extremely long legs, hence the grou ...

is a prop to support pottery in a kiln so that pottery does not touch each other or kiln's floor. In archaeology, they may be upside-down baked clay tripods, leaving characteristic marks at the bottoms of the pottery/porcelain. They expose the bottom of the fired piece to the full heat. Other types of furniture and furniture systems include kiln cars, kiln shelves, batts, tiles, and plates; tubes and beams; props and fittings, profile setters, rollers, stools; T-cranks, Y-cranks, pin cranks.Kiln furniture
IPS Ceramics The design of kiln furniture system depends of the wares manufactured: structural clay products, dinnerware, tiles, electronics ceramics, sanitaryware, electrical porcelain, etc.

References

{{reflist Pottery Kilns Firing techniques