Alloy 48
A nickel-iron controlled-expansion alloy containing 48% nickel. Its coefficient of thermal expansion is designed to match that of soft lead and soda-lime glasses. The alloy also has a high inflection point. Used for glass-to-metal seals in radio valves and incandescent electric light bulbs and for industrial thermostats that operate at temperatures up to 840°F (450°C).
Alloy 48 Chemistry maximum % unless noted
| Fe | Ni | Co | C | Si | S | Cr |
|---|---|---|---|---|---|---|
| Bal | 48 | -- | 0.05 | 0.30 | 0.02 | 0.025 |
Physical Properties
| Brand | Density | Melting point |
|---|---|---|
| Alloy 48 | 8.20 g/cm³ | 1450°C |
Applications
Super alloy 48 is suitable for usage in industrial thermostats operating at temperatures up to 450°C (840°F). This alloy is also used for glass-to-metal seals in incandescent electric light bulbs and radio valves.