Nickel alloys
Nickel is used as both a principal component and an alloying element in wrought and cast alloys.
- Low-Alloy nickel alloyed with manganese is stronger than pure nickel based on the same elongation. Silicon reduces the sensitivity to carburising and sulphurous gases.
- Nickel-Copper alloys (nickeline, constantan) benefit from excellent cold formability and their Strength increases along with the proportion of nickel. Adding manganese and Iron encourages solid solution strengthening, while adding Aluminium or Titanium enables precipitation Hardening. Such alloys exhibit excellent Resistance to stress-Corrosion cracking and pitting corrosion.
- The Thermal expansion of nickel-iron alloys depends on the nickel content. A minimum of approximately $2\cdot {{10}^{-6}}/K$ is reached at 36% Ni (Invar Steel). These alloys are easy to magnetise and demagnetise.
- Nickel-chromium alloys (Nimocast, Nimonic) form a Scale layer that makes them resistant to hot gases, even in the case of lengthy contact. Examples of alloys with enhanced resistance to alternating thermal stresses include nickel-aluminium alloys.