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List of Alloys & profiles

List of Alloys & profiles

Alloy Wire International

Datasheet: Nilo® 48

Nilo® 48

A Nickel-Iron, controlled expansion alloy containing 48% Nickel. Its coefficient of thermal expansion was designed to match that of soft lead and soda-lime glasses. This alloy also has a high inflection point. Nilo® 48 is often used in industrial thermostat rods up to 450°C (840°F) and for glass-to-metal seals in a number of applications, which may include radio valves and electric lamps.

Nilo® 48 is also known as Invar 48 and Magnifer 50.

Available in all profile options

Nilo® 48 - Alloy Wire International 1

Key Features

Nilo® 48 offers the following key features:

Coefficient of thermal expansion designed to match that of soft lead and soda-lime glasses.
High inflection point.

Typical Applications

Nilo® 48 is known to be suitable for the following applications:

Industrial thermostats that operate at temperatures up to 450°C (840°F).
Glass to metal seals


W.NR 1.3922
W.NR 1.3926
W.NR 1.3927
UNS K94800
AWS 092



Chemical Composition

The chemical composition of Nilo® 48 is indicated in the table below:

ElementMin %Max %
Ni48.00 nominal

Alloy Details

Nilo® 48 density, melting point, inflection point, thermal conductivity, and coefficient of expansion is indicated in the table below:

DensityMelting PointInflection PointThermal ConductivityCoefficient of Expansion
8.2 g/cm³1450 °C460 °C16.7 W/m• °C
8.5 µm/m °C (20 – 100 °C)
8.3 – 9.3 µm/m °C (20 – 300 °C)
0.296 lb/in³2640 °F860 °F116 btu•in/ft2•h °F4.7 x 10-6 in/in °F (70 – 212 °F)
4.6 – 5.2 x 10-6 in/in °F (70 – 572 °F)

Heat treatment of finished parts

The Nilo® alloys are usually supplied and used in the annealed condition (residual cold work distorts the coefficients of thermal expansion). Annealing times may vary due to section thickness.

The typical heat treatment of Nilo® 48:

Anneal850 – 1000 °C (1560 – 1830 °F)0.5 HrAir or water


The typical mechanical properties of Nilo® 48:

Approx. tensile strength<600 N/mm²<87 ksi
Approx. operating temperatureup to +450 °Cup to +840 °F
Hard Drawn
Approx. tensile strength700 – 900 N/mm²102 – 131 ksi
Approx. operating temperatureup to +450 °Cup to +840 °F

The above tensile strength ranges are typical. If you require different please ask.

*Trade name of Special Metals Group of Companies