Rare earth (RE) is the general name of 17 metal elements including lanthanide, scandium and yttrium in the periodic table of elements. Metallurgical workers at home and abroad began to study the action mechanism and industrial application technology of trace rare earth elements in steel very early, and found that rare earth elements can be used as deep purifier of steel, modifier of inclusions and important microalloying elements of high value-added steel materials. Cast steel is a non deformable material used to manufacture steel castings. In the production process of cast steel, there are strict requirements on the cleanliness and fluidity of molten steel, the morphology and distribution of inclusions in steel, the type of as cast structure and grain size, etc. trace rare earth elements have a good positive effect on these aspects. China is rich in rare earth resources. Developing high-quality rare earth cast steel is one of the important means to improve the properties of cast steel. In recent years, scholars at home and abroad have done a lot of work on the mechanism and application of rare earth in cast steel. This paper mainly summarizes and analyzes its research, in order to provide theoretical guidance for the preparation of rare earth cast steel products with excellent properties.
Adding trace rare earth elements to cast steel can play a good role in purifying liquid steel, modifying cast steel inclusions, improving as cast microstructure, microalloying and so on, and the comprehensive properties of cast steel can be improved to a certain extent. However, there are still many problems in practical production and application, such as the effective matching between rare earth addition and on-site process, the quantitative relationship between casting performance improvement and rare earth content, and so on, which still needs a lot of research work.