Nichrome 20 (UNS S31008 / W.Nr. 1.4843)

Nichrome 20 (UNS S31008 / W.Nr. 1.4843) is an austenitic nickel-chromium alloy for use at temperature up to 1050℃. The alloy is characterized by high resistivity and good oxidation resistance. It has good ductility after use and excellent weldability.

Equivalent Grades

Trademark	GB	GOST	ASTM	UNS	DIN	W.Nr.	NF	BS	JIS	SS
Nikrothal 20 Resistohm 20	Cr25Ni20	Х25Н20	310S	S31008	CrNi25 20	1.4843	–	–	–	–

Chemical Composition, %

Alloy	C	Si	Mn	P	S	Cr	Ni	Al	Fe
Nichrome 20	≤0.08	1.0-3.0	≤1.00	≤0.020	≤0.015	24.0-26.0	19.0-22.0	–	Bal

Mechanical Properties (RT, Annealed)

Tensile Strength, Rm/MPa	Elongation, A/%
Tensile Strength, Rm/MPa	Dia. >3.00mm (Wire) Thk. >0.20mm (Strip)	Dia. 0.10-3.00mm (Wire) Thk. ≤0.20mm (Strip)
≥600	≥25	≥20

Physical Properties

Max Working Temp., ℃	Melting Point, ℃	Density, g/cm3	Resistivity, μΩ·m 20℃	Specific Heat, J/(g•K)	Thermal Conductivity, W/(m•K) 20℃	Average Coefficient of Thermal Expansion,α×10-6/℃ 20-1000℃	Micrographic Structure	Magnetic Properties
1100	1390	7.90	1.04	0.50	13	19.0	Austenitie	Non-Magnetic

Life Test

Test Temperature, ℃	Continuous Service Time Hours, ℃
1100	≥80

Temperature Factor of Resistivity

20℃	100℃	200℃	300℃	400℃	500℃	600℃	700℃	800℃	900℃	1000℃	1100℃	1200℃	1300℃
1.00	1.04	1.10	1.14	1.17	1.21	1.23	1.26	1.28	1.30	1.32	1.34	–	–

Available Products and Specifications

Rod, Bar, Wire and Forgings	GB/T 1234-2012, ASTM B344-01, DIN 17470-1984
Plate, Sheet and Strip	GB/T 1234-2012, ASTM B344-01, DIN 17470-1984
Pipe and Tube	–
Welding Product	–
Others	–