Ni3Mo

Ni3Mo is an intermetallic compound with the chemical formula Ni3Mo, forming in nickel–molybdenum alloys. It is an ordered phase that can precipitate from Ni-rich solid solutions during aging heat treatments, acting as a strengthening phase in precipitation-hardened nickel alloys.

Ni3Mo exhibits an ordered intermetallic crystal structure typical of Ni3X compounds. It is relatively hard and has high-temperature stability, contributing to improved creep resistance. Ductility is generally limited, and the phase can be brittle at room temperature, with its strength influenced by particle size and distribution.

Formation and microstructure: Ni3Mo appears as fine precipitates dispersed in a Ni-based matrix. Its formation depends on alloy composition, heat-treatment temperature, and time. Coarsening of Ni3Mo particles under prolonged high-temperature exposure can affect toughness and softening resistance.

Applications and limitations: In practice, Ni3Mo is used to strengthen nickel alloys through precipitation hardening, especially where high-temperature strength is required. However, its brittleness and processing sensitivity limit broad industrial use, and it is often studied mainly in research and specialized alloys rather than as a bulk phase.

See also: Ni-Mo phase diagram; nickel-based superalloys; intermetallic compound; precipitation hardening.