Beryllide is an intermetallic compound of beryllium with other metals, e.g. zirconium, tantalum, titanium, nickel, or cobalt.
These are hard, metal-like materials that display properties distinct from the constituents, especially with regards to their resilience toward oxidation.
Beryllides of cobalt and nickel have metallurgical importance as the precipitated phase in beryllium copper alloys.
In nuclear technology, beryllides are investigated as neutron multipliers.
Unlike metallic Be, materials such as Be12Ti are more resistant to oxidation by water but retain the neutron-multiplying properties of the predominant isotope 9Be.