Invar alloy,ASTM F1684,UNS k93600(FeNi36),Chinese 4J36
A Nickel-Iron, low expansion alloy containing 36% Nickel. It maintains nearly constant dimensions over the range of normal atmospheric temperatures.
Forms: Sheet/Plate, Bar/Rod/Wire/Coil,Capillary/Pipe/Tube

Description

Invar (also know as Invar 36, NILO 36, Pernifer 36, and Invar Steel) is a low expansion alloy consisting of 36% Nickel, balance Iron. Invar Alloy exhibits extremely low expansion around ambient temperatures, making Invar Alloy particularly useful in applications where minimum thermal expansion and high dimensional stability is required, such as in precision instruments like optoelectronic devices, optical and laser benches, electronics, and other kinds of scientific instruments.

Application

This alloy has been used for applications where dimensional changes due to temperature variation must be minimized such as in radio and electronic devices, aircraft controls, optical and laser system, etc.

parameter

Cross Reference

Russia	USA	Japan	France	Germany	U.K.
36H	Invar	Cactus LE	Invar Standard	Vacodil36	Invar
	Nilvar				Nilo36
36H-ВИ	Unipsan36		Fe-Ni36	Nilos36	36Ni

Typical chemistry

C	Si	P	S	Mn	Ni	Fe
≤
0.05	0.30	0.020	0.020	0.20~0.60	35.0~37.0	Balance

Typical Physical Properties

Density	lb/cu in	0.291
Specific Gravity		0.825
Curie Temp	°F	535
	°C	279
Melting Point	°F	2600
	°C	1427
Electrical	Micro-ohm-cm	84
Resistivity	Micro-ohm-cm	495
Thermal	W/cm °C	0.10
Conductivity	BTU-in/sq. ft-hr-	72.6
Specific Heat	Cal/g- °C	0.123
	BTU/lbm- °F	0.123

Average Coefficient of Linear Expansion

Heat Treatment of the Samples	Mean Coefficient of Linear Expansion
	20 to l00℃	20 to 300℃
To heat the semi-finished products samples to 840±10°C, hold for1hour, and quench in the water. Machine the samples to finished samples. And heat at 315±10℃ for 1h, furnace or air cool.	1.5(max)

Mean Coefficient of linear expansion at different temperature, ā/(10^-6/K)

Size Range

Sheet	Thickness:0.10mm~3.50mm, width: ≤300mm
Plate	Thickness:3.5mm~40.0mm, width: ≤500mm
Round wire	Thickness:0.10mm~5.0mm
Flat Wire	Dia 0.5mm~Dia 5.0mm, length≤1000
Rod	Dia 5.0mm~Dia 8.0mm, length≤2000
	Dia 8.0mm~Dia 32.0mm, length≤2500
	Dia 32.0mm~Dia180.0mm, length≤1000
Capillary	OD 8.0mm~1.0mm,ID 0.1~8.0 length≤2500
Pipe	OD 120mm~8.0mm,ID 8.0~129 length≤4000

Condition: (With max tolerance) cold rolled, cold drawn, hot rolled , hot forging ,peeled turned ,bright ,bright annealed