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As a Precious Metal Contract Manufacturer Nordt EPM offers:
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Low Thermal Expansion Alloys



Invar
Invar, also known generically as FeNi36 (64FeNi in the US), is a nickel steel alloy notable for its uniquely low coefficient of thermal expansion. As with other nickel/iron compositions, Invar is a solid solution; that is, it is a single-phase alloy — similar to a dilution of common table salt mixed into water. "Invar" refers to invariable; that is, it will not react to thermal expansion.[1]
Variations of the original Invar material that have slightly different coefficient of thermal expansion such as:
- Inovco, which is Fe-33Ni-4.5Co has an α (20–100 °C) of 0.55 ppm/°C.
- NILO alloy 42FeNi42 has a nickel content of 42% and α ≈ 5.3 ppm/°C which matches that of silicon and therefore is widely used as lead frame material for electronic components, integrated circuits, etc.
- Kovar or Dilver P / FeNiCo alloys have the same expansion behavior as borosilicate glass, and because of that are used for optical parts in a wide range of temperatures and applications, such as satellites.
Shape Memory Alloys


Nitinol
Nickel titanium (NiTi) is a shape memory alloy also commonly referred to by the name Nitinol. It has been found that shape memory alloys can recover substantial amounts of strain, and/or generate significant force, when changing shape.
Above its transformation temperature, Nitinol is superelastic, able to withstand a small amount of deformation when a load is applied and return to its original shape when the load is removed. Below its transformation temperature, it displays the shape memory effect. When it is deformed it will remain in that shape until heated above its transformation temperature, at which time it will return to its original shape.
Nitinol is typically composed of approximately 50 to 55.6% nickel by weight.
Other Shape memory Alloys (SMA)
- CuSn Copper Tin
- InTi Indium Titanium
- MnCu Manganese Copper


