Iron Chrome Aluminum Resistance Alloys
Iron Chrome Aluminum (FeCrAl) alloys are high-resistance materials typically used in applications with maximum operating temperatures up to 1,400°C (2,550°F).
These Ferritic alloys are known to have higher surface loading capability, higher resistivity and lower density than Nickel Chrome (NiCr) alternatives which can translate to less material in application and weight savings. The higher maximum operating temperatures can also lead to longer element life. Iron Chrome Aluminum alloys form a light grey Aluminum Oxide (Al2O3) at temperatures above 1,000°C (1,832°F) which increases corrosion resistance as well as acts as an electrical insulator. The oxide formation is considered self-insulating and protects against short circuiting in the event of metal to metal contact. Iron Chrome Aluminum alloys have lower mechanical strength when compared to Nickel Chrome materials as well as lower creep strength.
Hyndman Industrial Products offers a variety of Iron Chrome Aluminum alloys and keeps the most common in inventory.
KAF: Common Name: Kanthal AF, Resistohm Y, Aluchrom Y, Alloy 837, AF
Ideal choice when you need good form stability at elevated temperatures. Uses: Open mica elements for toasters and hair dryers, meander shaped elements for fan heaters, open coil elements on fiber insulating material, ceramic glass top heaters in ranges, boiling (hot) plates, suspended coil and straight wire elements for radiators, convection heaters, as porcupine elements for hot air guns, radiators, and tumble dryers.
KAPM: Common Name: Alloy 875 PM, Kanthal APM
Typical applications are in furnaces for firing of high temperature ceramics, heat treatment furnaces, laboratory furnaces, diffusion furnaces, and high temperature kilns. Produced from powder metallurgy technology this alloy has demonstrated significant improvements in both physical and mechanical properties. Its advantages are better form stability, high temperature strength, and the ability to be self-supporting at temperatures above 1300º C. It has an excellent surface oxide, which gives good protection in corrosive atmospheres as well as in atmospheres with high carbon potential, and no scaling.
ALK: Common Name: Alkrothal 14, Alloy 750, Alferon 902, Alchrome 750, Resistohm 125, Stablohm 750
Relatively low-temperature applications such as heating cables, resistors, terminal pins, etc.
KD: Common Name: Kanthal D, Alloy 815, Alchrome DK, Alferon 901, Resistohm 135, Aluchrom 5, Stablohm 812
Metal sheathed tubular elements, elements embedded in ceramics for panel heaters, cartridge heaters, heating cables and rope heaters for defrosting and de-icing, mica elements used in irons, quartz tube heaters for space heating, infrared dryers, heating plates, ceramic hobs, bead insulated coils for panel heaters, air heaters, laundry dryers, furnace element terminals, porcupine elements, and furnace heating elements.
KA1: Common Name: Kanthal A1, Alloy 875, Resistohm 145, Alchrome 875, MWS-875, Stablohm 875
Primarily used for industrial furnaces, kilns, and other equipment with the highest continuous operating temperatures such as heat treating, ceramics, glass, steel, aluminum, and the electronics industries. Alloy is less susceptible to distortion, growth, and increase in resistance when heated than other alloys of similar composition. While quite resistant to sulfur corrosion, this alloy is not recommended for use in reducing atmospheres other than dry hydrogen.