Electroless nickel-boron plating
Electroless nickel-boron coating (often called NiB coating) is a metal plating process that can create a layer of a nickel-boron alloy on the surface of a solid substrate, like metal or plastic. The process involves dipping the substrate in a water solution containing nickel salt and a boron-containing reducing agent, such as an alkylamineborane or sodium borohydride.
Source: Wikipedia — Electroless nickel-boron plating (CC BY-SA 4.0)