Alkrothal 720 No.1 JR for brake resistor
Typical applications for Alkrothal 720 are in rheostats, braking resistors, etc. It is also used as electrical heating elements in industrial applications.
Alkrothal 720 is a ferritic iron-chromium-aluminium alloy (FeCrAl alloy) for use at temperatures up to 1000°C (1830°F).
Nominal Analysis
Cr | Al | Fe |
12.0~15.0 | 4.0~6.0 | Balance |
Mechanical Properties
Max Continuous Service Temperature: Resisivity 20ºC: Density: Thermal Conductivity: Coefficient of Thermal Expansion: Melting Point: Elongation: Micrographic Structure: Magnetic Property: |
950ºC 1.25ohm mm2/m 7.40g/cm3 52.7 KJ/m·h·ºC 15.4×10-6/ºC (20ºC~1000ºC) 1450ºC Min 16% Ferrite magnetic |
Size: Thickness 0.01-7mm, width 0.5-1000mm
Surface: BA, 2B
Hardness: Soft, Half hard, hard
Has been used extensively as big power brake resisor and furnace heating elements.
Has less hot strength than Tophet alloys but much higher melting point.
Shanghai TANKII ALLOY MATERIAL Co., Ltd.
FECRAL AND ALCHROME ALLOY PRODUCER IN China, MOST PROFESSIONAL IN THE WORLD
We also produce below grades:
0Cr15Al5 and 0Cr19Al3, etc.
Chemical Composition and Main Property of Fe-Cr-Al Resistance Alloy | ||||||||
Properties Grade | 1Cr13Al4 | 0Cr25Al5 | 0Cr21Al6 | 0Cr23Al5 | 0Cr21Al4 | 0Cr21Al6Nb | 0Cr27Al7Mo2 | |
Main Chemical Composition (%) |
Cr | 12.0-15.0 | 23.0-26.0 | 19.0-22.0 | 22.5-24.5 | 18.0-21.0 | 21.0-23.0 | 26.5-27.8 |
Al | 4.0-6.0 | 4.5-6.5 | 5.0-7.0 | 4.2-5.0 | 3.0-4.2 | 5.0-7.0 | 6.0-7.0 | |
Re | opportune | opportune | opportune | opportune | opportune | opportune | opportune | |
Fe | Bal. | Bal. | Bal. | Bal. | Bal. | Bal. | Bal. | |
Nb0.5 | Mo1.8-2.2 | |||||||
Max Continuous Service Temperature(oC) | 950 | 1250 | 1250 | 1250 | 1100 | 1350 | 1400 | |
Resisivity 20oC (Ωmm2/m) | 1.25 ±0.08 |
1.42 ±0.06 |
1.42 ±0.07 |
1.35 ±0.07 |
1.23 ±0.07 |
1.45 ±0.07 |
1.53 ±0.07 |
|
Density(g/cm3) | 7.4 | 7.1 | 7.16 | 7.25 | 7.35 | 7.1 | 7.1 | |
Thermal Conductivity | 52.7 | 46.1 | 63.2 | 60.2 | 46.9 | 46.1 | 45.2 | |
(KJ/m@h@oC) | ||||||||
Coefficient of Thermal Expansion(α×10-6/oC) | 15.4 | 16 | 14.7 | 15 | 13.5 | 16 | 16 | |
Approximate Melting Point( oC) | 1450 | 1500 | 1500 | 1500 | 1500 | 1510 | 1520 | |
Tensile Strength(N/mm2) | 580-680 | 630-780 | 630-780 | 630-780 | 600-700 | 650-800 | 680-830 | |
Elongation(%) | >16 | >12 | >12 | >12 | >12 | >12 | >10 | |
Section Variation | 65-75 | 60-75 | 65-75 | 65-75 | 65-75 | 65-75 | 65-75 | |
Shrink Rate (%) | ||||||||
Repeatedly Bend Frequency(F/R) | >5 | >5 | >5 | >5 | >5 | >5 | >5 | |
Hardness (H.B.) | 200-260 | 200-260 | 200-260 | 200-260 | 200-260 | 200-260 | 200-260 | |
Continuous Service Time | no | ≥80/1300 | ≥80/1300 | ≥80/1300 | ≥80/1250 | ≥50/1350 | ≥50/1350 | |
Micrographic Structure | Ferrite | Ferrite | Ferrite | Ferrite | Ferrite | Ferrite | Ferrite | |
Magnetic Property | Magnetic | Magnetic | Magnetic | Magnetic | Magnetic | Magnetic | Magnetic |