Ferroniobium is an iron alloy composed mainly of niobium and iron. It also contains impurities such as aluminum, silicon, carbon, sulfur, and phosphorus. According to the niobium content of the alloy, it is divided into FeNb50, FeNb60, and FeNb70. The iron alloy produced from niobium tantalum ore contains tantalum, known as niobium tantalum iron.