Invar® 42 is a nickel-iron, controlled-expansion alloy containing 42 percent nickel. It has a low and nominally constant coefficient of thermal expansion form room temperature to about 570°F (300°C). Invar® 42 is used for semiconductor lead frames in integrated circuits, bi-metal thermostat strip, thermostat rods, for ceramic-to-metal seals with alumina ceramics, and various glass-to-metal seals such as the core of copper-clad wire for sealing into glass envelopes of electric bulbs, radio valves, television tubes and fluorescent lights. Standard product forms are tube, sheet, strip and wire.
Unit of Measure

Specifications

Material

N/A Invar®

Shapeform

N/A Plates

Thickness

N/A 1/2 inches

Thickness

N/A 0.500 inches12.7 mm

Nickel Alloy Compositions

Alloy

N/A Invar® 42

Basic Composition

N/A 42.0 % Nickel 58.0% Iron

Density

N/A 0.293 lbs/in³8.11 g/cm³

ASTM Specification

N/A ASTM F30 UNS K94100

Typical Mechanical Properties

Tensile Strength

N/A 71000 psi490 MPa

Yield Strength (0.2% Offset)

N/A 36000 psi250 MPa

Elongation

N/A 43 %

Melting Temperature Range

N/A 2615 ºF1435 ºC