Nikrothal® 70

StripDatasheet

Datasheet updated 2024-09-05 12:01 (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^®.

Nikrothal^® 70 strip is an austenitic nickel-chromium alloy (NiCr alloy) for use at temperatures up to 1250°C (2280°F). The alloy is characterized by high resistivity and good oxidation resistance. It has good ductility after use and excellent weldability.

Nikrothal^® 70s strip is particularly well suited for reducing atmospheres, as it is not subject to 'green rot'.

Typical applications for Nikrothal^® 70 are as electrical heating elements in industrial furnaces.

Chemical composition

	C %	Si %	Mn %	Cr %	Fe %	Ni %	Trace elements
Nominal Composition	-	-	-	-	-	Bal.	Added
Min	-	0.5	-	29.0	-	-	-
Max	0.15	2.0	1.0	32.0	5.0	-	-

Mechanical properties

Strip Thickness	Yield Strength	Tensile strength	Elongation	Hardness
	R_p0.2	R_m	A
mm	MPa	MPa	%	Hv
1.0	450	875	30	185
1.5	380	715	45	185

Mechanical properties at elevated temperature
Temperature °C	900
MPa	100

Ultimate tensile strength - deformation rate 6.2 x 10 -2 min -1

Creep strength - 1% elongation in 1000 h
Temperature °C	800	1000
MPa	15	4

Physical properties

Density g/cm³	8.10
Electrical resistivity at 20°C Ω mm²/m	1.18

Temperature factor of resistivity
Temperature °C	100	200	300	400	500	600	700	800	900	1000	1100	1200
Ct	1.01	1.02	1.03	1.04	1.05	1.05	1.04	1.04	1.04	1.05	1.05	1.06

Coefficient of thermal expansion
Temperature °C	Thermal Expansion x 10^-6/ K
20 - 250	14
20 - 500	15
20 - 750	16
20 - 1000	17

Thermal Conductivity
Temperature °C	20	100	200	300	400	500	600	700	800	900	1000	1100
W m^-1 K^-1	13	13	14	15	17	19	20	22	24	26	28	29

Specific heat capacity
Temperature °C	20	100	200	300	400	500	600	700	800	900	1000	1100
kJ kg^-1 K^-1	0.46	0.46	0.48	0.50	0.53	0.55	0.58	0.60	0.63	0.65	0.67	0.71

Melting point °C	1380
Max continuous operating temperature in air °C	1250
Magnetic properties	The material is non-magnetic.
Emissivity - fully oxidized material	0.88