A large portion of the world's niobium is used in the production of nickel, chromium, and iron-based superalloys in the form of pure metal or in the form of high purity iron and nickel niobium alloys. These alloys can be used in jet engines, gas turbine engines, rocket assemblies, turbochargers and heat-resistant combustion equipment. Niobium forms a long phase in the grain structure of superalloys. Such alloys typically contain up to 6.5% niobium. Inconel 718 is one of the niobium-based alloys containing nickel 50%, chromium 18.6%, iron 18.5%, niobium 5%, molybdenum 3.1%, titanium 0.9% and aluminum 0.4%. Applications include as high end body materials such as those used in Gemini programs.
The c-103 is an alloy of niobium containing 89 per cent niobium, 10 per cent hafnium and 1 per cent titanium, and can be used in liquid rocket thrusters such as the Apollo lunar module's main engine. The Apollo service module USES another niobium alloy. Since niobium begins to oxidize above 400°C, a protective coating must be applied to the surface to prevent it from becoming brittle.
These alloys can be melted into particles or flakes. Huachang had hafnium, an element made from a nuclear-grade zirconium alloy, and wanted to develop it for commercial use. The nb-10hf-1ti alloy in series C, which has the so-called 103 component ratio, has the best balance between die forging and high temperature properties, so huachang produced the first 500-pound c-103 alloy in 1961 using VAR and EBM methods for turbine engine components and liquid metal heat exchangers. Other niobium alloys in the same period include FS85(nb-10w-28ta-1zr) from fenstill metallurgical corporation.
