High-throughput search for RE (La, Ce and Y) contained stoichiometric compound in steels

Abstract

The design of rare earth (RE) bearing steels requires a thorough understanding of the formation tendency of RE involved phases in steels, while searching for binary and ternary compounds with a wide variety of composition and permutation need a remarkable amount of experimentation which is nearly infeasible. In the present work, we perform a thorough search for the RE-contained compounds in steels by a data-driven high-throughput computational approach. The search results indicate that RE may react with O and N to form a large amounts of oxide and nitride inclusions, while only Y participate in the formation of sulfide inclusion Y2MnS4 and Y2CaS4. For the case of ternary compounds in Fe-based solid solution, it is found that RE prefers to form ternary phases with the non-metallic elements, i.e., B, C, O, P and Si, and only Y is found to combine with metal Cr to form YCr4Fe8. Finally, our screen suggests that RE can participate in the formation of the nano-scale precipitates of κ-carbides, L12 precipitates and B2 precipitates, but MC and M2C carbides.