Alloy 36

┃ Material

Alloy 36, Invar 36, FeNi36, 1.3912, K93600, K93601, K93602, K93603, K93050, 1J36, 4J36

 

┃ Overview

Alloy 36 is a binary iron-nickel alloy with a particularly low heat expansion coefficient, whereby the levels of carbon and manganese as well as freedom of impurities are significant. Cold forming also reduces the heat expansion. Artificial aging with gradual heat treatment stabilizes the expansion coefficients in a selected temperature range.

 

┃ Characteristics

◇ An extremely low expansion coefficient between -250°C (-418°F) and +260°C (500°F)

◇ Good ductility and toughness.

 

┃ Typical applications

◇ Piping for storage and transport of liquefied gases

◇ Components for OLED screens

◇ Measuring and control devices for temperatures below 200°C (392°F), e.g. for thermostats

◇ Bushings for screw or rivet joints between various metals

◇ Bi-metal components and thermostatic bi-metals, where Alloy 36 is the passive component

◇ Forms for the production of carbon-fiber reinforced plastic (CFP), especially for the aerospace industry

◇ Frameworks for electronic control units in satellites and space travel down to -200°C (-328°F)

◇ Support elements for electro-magnetic lenses in laser control units

◇ Pendulum

◇ Components for the automotive industry

◇ Overhead power lines in an alloyed, age-hardenable variant

 

┃ Chemical composition (wt%)

Material	Ni	Fe	Co	Mn	Si	C	Al
Alloy 36	35.0~37.0	balance	≤0.50	≤0.60	≤0.40	≤0.05	≤0.10
Material	Mg	Zr	Ti	Cr	P	S
Alloy 36	≤0.10	≤0.10	≤0.10	≤0.25	≤0.015	≤0.015

 

┃ Typical Mechanical Properties of Alloy 36

Soft annealed condition

Temperature		Tensile Strength		Yield Strength (0.2% Offset)		Elongation on 50 mm (2 inch)	Reduction of Area
°C	°F	MPa	ksi	MPa	ksi	%	%
20	68	490	71	240	35	42	70
100	212	430	62	180	26	43	70
200	392	430	62	110	16	45	70
300	572	410	59	93	13	48	70
400	752	350	51	93	13	53	70
500	932	290	42	93	13	59	69
600	1112	210	30	77	11	68	67

Hardness

Annealed: 150 HV (80HRB) max.

Full hard: 220 HV (96HRB) min.

┃ Corrosion resistance

In a dry atmosphere, Alloy 36 is corrosion resistant at room temperature. In unfavorable conditions, for example a humid atmosphere, corrosion may occur on the surface.

┃ Heat treatment

The annealing should be performed at temperatures of 820 to 900°C (1580-1652°F), followed by air cooling. Compared with air cooling, water cooling following annealing results in a lower heat expansion coefficient. However, the resulting microstructure is not stable. Following cold forming of less than 10%, the annealing temperature should not exceed 860°C (1580 °F).

 

┃ Available Process

(1) Hot formed, annealed, descaled

(2) Cold worked and bright annealed

(3) Cold worked, aged, polished (MP, EP etc.)

 

┃ Common Tests

Chemical composition

Tension

Hardness

Flaring

Flange

Flattening

Micro structure

Hydrostatic

NDT

Intergranular Corrosion

Surface condition

Shape and dimension

Positive Material Identification