A nickel-iron-cobalt controlled-expansion alloy containing 29% nickel. Its coefficient of expansion, which decreases with rising temperature to the inflection point, matches the expansion rate of borosilicate glasses and alumina ceramics. Used for glass-to-metal seals in applications requiring high reliability or resistance to thermal shock. Examples are high-power transmitting valves, transistor leads and headers, integrated-circuit lead frames, and photography flash bulbs.
Stock program
Wire, cold drawn, annealed, coil
kg /
m
Ø
4.75 mm
0.15
Limiting
Fe¹
53.00
%
Ni¹
29.00
%
Co¹
17.00
%
Mn
max.
0.50
%
Cr
max.
0.20
%
Cu
max.
0.20
%
Mo
max.
0.20
%
Si
max.
0.20
%
Al
max.
0.10
%
Mg
max.
0.10
%
Ti
max.
0.10
%
Zr
max.
0.10
%
C
max.
0.04
%
¹
Nominal value; adjusted to meet expansion requirements
