Iron-based alloys (Fe-based) are widely used in hard-facing materials. The biggest characteristics of this kind of material are good comprehensive performance, wide range of performance and the lowest price. Iron-based alloy refers to the alloy formed by adding other alloying elements on the basis of iron. Steel is often classified according to its carbon content. Steel is an iron-carbon alloy with low carbon content, which will form face-centered cubic austenite when heated. If the carbon content is too high and austenite does not appear during heating to melting, it is called iron (cast iron). If the carbon content is particularly low, it exists as ferrite at room temperature (no cementite is precipitated), which is called industrial pure iron. The above is aimed at the iron-carbon binary alloy system. For steel, other alloying elements are generally added to obtain different properties, such as spring steel and high speed steel. These are also austenitic iron-based alloys containing carbon (usually low carbon content), which form FCC structure during heating. Generally speaking, steel/iron is used to refer to iron-based alloys (see above for the method of distinguishing steel/iron), and "iron-based alloys" generally emphasize their special properties, such as "high temperature alloys".

Iron-based amorphous alloy or metallic glass is a new material that appeared in 1970s. It is a material that molten steel is formed into a thin strip with a thickness of 30 microns at one time by rapid cooling technology, and the obtained solid alloy (thin strip) is different from the crystal structure of atoms arranged regularly in cold-rolled silicon steel materials. It is precisely because the atoms of this alloy are in an amorphous structure with random arrangement that it has a narrow B-H ring, high permeability and low loss. At the same time, the irregular arrangement of atoms in amorphous alloys limits the free passage of electrons, resulting in a resistivity 2-3 times higher than that of crystalline alloys, which is also conducive to reducing eddy current loss. Compared with the traditional silicon steel sheet transformer, the no-load loss of amorphous alloy transformer core is reduced by about 75%, which makes amorphous alloy transformer have very remarkable energy saving and environmental protection effects. When amorphous alloy transformer core is used in oil-immersed transformer, it can obviously reduce many harmful gases. Therefore, more and more manufacturers use amorphous alloy as the raw material of transformer core.