Kanthal® A-1

Resistance heating wire and resistance wireDatasheet

Datasheet updated 2024-09-05 11:06 (supersedes all previous editions)

Disclaimer: Recommendations are for guidance only, and the suitability of a material for a specific application can be confirmed only when we know the actual service conditions. Continuous development may necessitate changes in technical data without notice. This datasheet is only valid for materials under the trademark Kanthal^®.

Kanthal^® A-1 wire is a ferritic iron-chromium-aluminium alloy (FeCrAl alloy) for use at temperatures up to 1400°C (2550°F). The alloy is characterized by high resistivity and very good oxidation resistance.

Typical applications for Kanthal^® A-1 are electrical heating elements in high-temperature furnaces for heat treatment, ceramics, glass, steel, and electronics industries.

Chemical composition

	C %	Si %	Mn %	Cr %	Al %	Fe %
^†Nominal composition					5.8	Bal.
Min	-	-	-	20.5	-
Max	0.08	0.7	0.4	23.5	-

^†Note: Composition listed is nominal. Actual composition may vary to meet standard electrical resistance and dimensional tolerances.

Mechanical properties

Wire size	Yield strength	Tensile strength	Elongation	Hardness
Ø	R_p0.2	R_m	A
mm (in)	MPa (ksi)	MPa (ksi)	%	Hv
1.0 (0.04)	545 (79)	760 (110)	20	240
4.0 (0.16)	475 (69)	680 (99)	18	230

Mechanical properties at elevated temperature
Temperature °C	900	1000	1100	1200	1300
Temperature °F	1652	1832	2012	2192	2372
MPa	34	18	10	6	4
ksi	4.9	2.6	1.5	0.9	0.6

Ultimate tensile strength - deformation rate 6.2 x 10^-2/min

Creep strength - 1% elongation in 1000 h
Temperature °C	800	1000
Temperature °F	1472	1832
MPa	1.2	0.5
psi	170	73

Physical properties

Density g/cm³ (lb/in³)	7.10 (0.257)
Electrical resistivity at 20°C Ω mm²/m (Ω circ. mil/ft)	1.45 (872)
Poisson's ratio	0.30

Young's modulus
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 factor of resistivity
Temp. °C	100	200	300	400	500	600	700	800	900	1000	1100	1200	1300	1400
Temp. °F	212	392	572	752	932	1112	1292	1472	1652	1832	2012	2192	2372	2552
Ct	1.00	1.00	1.00	1.00	1.01	1.02	1.02	1.03	1.03	1.04	1.04	1.04	1.04	1.05

Coefficient of thermal expansion
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)

Thermal conductivity
Temperature °C	50	600	800	1000	1200	1400
Temperature °F	122	1112	1472	1832	2192	2552
W m^-1 K^-1	11	20	22	26	27	35
Btu h^-1ft^-1°F^-1	6.4	11.6	12.7	15.0	15.6	20.2

Specific heat capacity
Temperature °C	20	200	400	600	800	1000	1200	1400
Temperature °F	68	392	752	1112	1472	1832	2192	2552
kJ kg^-1 K^-1	0.46	0.56	0.63	0.75	0.71	0.72	0.74	0.80
Btu lb^-1 °F^-1	0.11	0.13	0.15	0.18	0.17	0.17	0.18	0.19

Melting point °C (°F)	1500 (2732)
Max continuous operating temperature in air °C (°F)	1400 (2552)
Magnetic properties	The material is magnetic up to approximately 600°C (1112°F) (Curie point).
Emissivity - fully oxidized material	0.70