Nickel-Chromium and Nickel-Chromium-Iron Alloys

• Nickel-chromium and nickel-chromium-iron resistance wires have the following characteristics:
• - High resistance: Nickel-chromium and nickel-chromium-iron resistance wires have higher resistance values, which enables them to generate heat when an electric current passes through.
• - Good temperature resistance: These resistance wires can withstand high temperatures without significant degradation in performance. They are commonly used in applications where high-temperature resistance is required.
• - Stable resistance: The resistance of nickel-chromium and nickel-chromium-iron resistance wires remains relatively stable over time and does not change significantly with temperature or other factors.
• - Corrosion resistance: These resistance wires are relatively resistant to corrosion, making them suitable for use in harsh environments or where exposure to moisture or chemicals is likely.
• - Long service life: Nickel-chromium and nickel-chromium-iron resistance wires typically have a long service life and can withstand repeated heating and cooling cycles without significant deterioration.

These characteristics make nickel-chromium and nickel-chromium-iron resistance wires widely used in applications such as heating elements, resistive heating, industrial processes, and temperature measurement. The specific choice between nickel-chromium and nickel-chromium-iron resistance wires depends on the specific requirements of the application, including temperature range, resistance value, and corrosion resistance needed. Especially Cr20Ni80 alloy has better comprehensive characteristics and it is the preferred type of high quality electric heating elements. All these products are widely used in industrial electric furnace, metallurgy, machinery, household appliances and other industries to produce heating components.

Main Properties and Characteristics of Nickel-Chromium and Nickel-Chromium-Iron Material

Alloy Name Properties		Cr20Ni80	Cr30Ni70	Cr15Ni60	Cr20Ni35	Cr20Ni30
Main Chemical Components	Ni	Remainder	Remainder	55.0-61.0	34.0-37.0	30.0-34.0
	Cr	20.0-23.0	28.0-31.0	15.0-18.0	18.0-21.0	18.0-21.0
	Fe	≤1.0	≤1.0	Remainder	Remainder	Remainder
Maximum operating temperature		1200	1250	1150	1100	1100
Resistivity 20ºC (μΩ·m)		1.09	1.18	1.12	1.0	1.04
Density(g/cm3)		8.40	8.10	8.20	7.90	7.90
Coefficient of heat conductivity (20ºC) (W/m·K)		15	14	13	13	13
Coefficient of linear expansion (20ºC ~ 1000ºC) (α×10-6/ºC)		18.0	17.0	17.0	19.0	19.0
Melting point(ºC)		1400	1380	1390	1390	1390
Tensile strength(Rm/MPa)		≥650	≥650	≥600	≥600	≥600
Elongation(%)		≥20	≥20	≥20	≥20	≥20
Accelerated life test(Hours/ºC)		≥80/1200	≥50/1250	≥80/1150	≥80/1100	≥50/1100
Microscopic structure		Austenite	Austenite	Austenite	Austenite	Austenite
Magnetism		Nonmagnetic	Nonmagnetic	Weak magnetic	Nonmagnetic	Nonmagnetic

The temperature correction factor for Nickel-Chrome and Nickel-Chrome-Iron alloys

Alloy Name	20	100	200	300	400	500	600	700	800	900	1000	1100	1200
	ºC	ºC	ºC	ºC	ºC	ºC	ºC	ºC	ºC	ºC	ºC	ºC	ºC
Cr20Ni80	1	1.006	1.012	1.018	1.025	1.026	1.018	1.01	1.008	1.01	1.014	1.021	1.025
Cr30Ni70	1	1.007	1.016	1.028	1.038	1.044	1.036	1.03	1.028	1.029	1.033	1.037	1.043
Cr15Ni60	1	1.011	1.024	1.038	1.052	1.064	1.069	1.073	1.078	1.088	1.095	1.109
Cr20Ni35	1	1.029	1.061	1.09	1.115	1.139	1.157	1.173	1.188	1.208	1.219	1.228
Cr20Ni30	1	1.023	1.052	1.079	1.103	1.125	1.141	1.158	1.173	1.187	1.201	1.214	1.226
– To obtain resistance at working temperature, multiply by the factor in above table.