US Patent 7399238 Iron golf club with nanocrystalline face insert

The iron golf club head (20) of the present invention is preferably composed of three main components: a periphery member 22, a central member 24 and a nanocrystalline plated face plate 26. The periphery member (22) is preferably composed of a high density material such as a nickel-tungsten alloy. The central member (24) is preferably composed of a lightweight, non-metal material. The face plate (26) is preferably composed of a non-metal material plated with a nanocrystalline material. The iron golf club head (20) preferably has high moments of inertia Izz and Ixx.