- Grade / Alloy
- Ni48
- EN / W.Nr.
- 1.3922
- AISI / SAE
- —
- UNS
- —
- Family
- Controlled expansion
Chemical composition
Chemical composition
Typical compositionTypical principal-element values for the alloy identified by its material number; not an expansion or magnetic-performance specification on their own.
| Element | Content (% by mass) |
|---|---|
| NiNickel | 48 |
| FeIron | 52 |
Values describe the grade, not the analysis of a specific batch. The applicable product specification and material certificate determine acceptance. A dash does not mean zero.
The principal feature of Ni48
The distinctive characteristic of Ni48 is its dimensional response to heating and cooling. A particular iron-nickel ratio produces this physical behaviour. Compatible movement matters in small joints between different materials as temperature changes. The alloy therefore serves electronic components where the metal needs to work together with glass within the connection.
Where glass meets metal
Glass-sealed electronic feedthroughs provide a clear example. Metal carries the electrical connection while glass can provide insulation and closure. If they move very differently with temperature, stress develops at the interface. Matching expansion helps reduce that effect. The properties of the particular glass are therefore as important as the physical response of the metal.
Distinction from Alloy 42 and Kovar
Alloy 42 contains less nickel than Ni48, while Kovar includes cobalt alongside iron and nickel. These differences produce expansion behaviours suited to different types of glass. The role of Ni48 is to provide the dimensional response required within a particular electronic connection. This explains why the same broad family includes several distinct options.
Expansion and magnetic characteristics
For Ni48, identified as 1.3922, controlled expansion is the priority in this application. Iron-nickel alloys also serve magnetic cores, where response to magnetic fields is central instead. Glass-to-metal connections focus on thermal dimensional movement. The use of related base metals for different physical characteristics illustrates the broad application range of these specialised alloys.
Typical application areas
Glass-to-metal connections, electronic feedthroughs, precision parts.
Product and cutting options
Relevant product forms for this material are listed below. Availability varies with grade and dimensions.