Alkrothal® 14 is a ferritic iron-chromium-aluminium alloy (FeCrAl alloy) with high resistivity suitable for use at temperatures up to 1100°C (2010°F).
Typical applications for Alkrothal® 14 are in rheostats, braking resistors, etc. It is also used as electrical heating elements in industrial applications.
Chemical composition
| C % | Si % | Mn % | Cr % | Al % | Fe % | |
|---|---|---|---|---|---|---|
| Nominal composition | 4.3 | Bal. | ||||
| Min | - | - | - | 14.0 | - | |
| Max | 0.08 | 0.7 | 0.5 | 16.0 | - |
Mechanical properties
| Thickness | Yield strength | Tensile strength | Elongation | Hardness |
|---|---|---|---|---|
| Rp0.2 | Rm | A | ||
| mm (in) | MPa (ksi) | MPa (ksi) | % | Hv |
| 1.0-3.0 (0.04-0.12) | 420 (61) | 550 (80) | 20 | 200 |
| Temperature °C (°F) | 900 (1652) |
|---|---|
| MPa (ksi) | 30 (4.4) |
Ultimate tensile strength - deformation rate 6.2 x 10 -2 min -1
| Temperature °C (°F) | 800 (1472) | 1000 (1832) |
|---|---|---|
| MPa (psi) | 4 (580) | 1 (150) |
Physical properties
| Density g/cm3 (lb/in3) | 7.28 (0.263) |
|---|---|
| Electrical resistivity at 20°C Ω mm2/m (Ω circ. mil/ft) | 1.25 (752) |
| Poisson's ratio | 0.30 |
| Temperature °C | 20 | 100 | 200 | 400 | 600 | 800 | 1000 |
|---|---|---|---|---|---|---|---|
| Temperature °F | 68 | 212 | 392 | 752 | 1112 | 1472 | 1832 |
| GPa | 220 | 210 | 205 | 190 | 170 | 150 | 130 |
| Msi | 32 | 30 | 30 | 28 | 25 | 22 | 19 |
| Temperature °C | 100 | 200 | 300 | 400 | 500 | 600 | 700 | 800 | 900 | 1000 | 1100 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Temperature °F | 212 | 392 | 572 | 752 | 932 | 1112 | 1292 | 1472 | 1652 | 1832 | 2012 |
| Ct | 1.00 | 1.02 | 1.03 | 1.04 | 1.05 | 1.08 | 1.09 | 1.10 | 1.11 | 1.11 | 1.12 |
| Temperature °C (°F) | Thermal Expansion x 10-6/ K (10-6 /°F) |
|---|---|
| 20 - 250 (68-482) | 11 (6.1) |
| 20 - 500 (68-932) | 12 (6.7) |
| 20 - 750 (68-1382) | 14 (7.8) |
| 20 - 1000 (68-1832) | 15 (8.3) |
| Temperature °C (°F) | 20 (68) |
|---|---|
| W m-1 K-1 (Btu h-1ft-1°F-1) | 16 (9.3) |
| Temperature °C | 20 | 200 | 400 | 600 | 800 | 1000 |
|---|---|---|---|---|---|---|
| Temperature °F | 68 | 392 | 752 | 1112 | 1472 | 1832 |
| kJ kg-1 K-1 | 0.46 | 0.63 | 0.72 | 1.00 | 0.80 | 0.73 |
| Btu lb-1 °F-1 | 0.11 | 0.15 | 0.17 | 0.24 | 0.19 | 0.17 |
| Melting point °C (°F) | 1500 (2732) |
|---|---|
| Max continuous operating temperature in air °C (°F) | 1100 (2012) |
| Magnetic properties | The material is magnetic up to approximately 600°C (1112°F) (Curie point). |
| Emissivity - fully oxidized material | 0.70 |
