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.

Thermodynamics of the Formation of Non-Metallic Inclusions during the Deoxidation of GCr15 Bearing Steel

“…As inclusions are distinctive from steel in terms of hardness, thermal expansion, deformability, and so on, they can easily cause stress concentrations and fatigue cracks in steel. Hence, scholars have carried out extensive research on reducing inclusions [6,7], inclusion modifications [8][9][10], inclusion formation thermodynamics [11][12][13], and clean deoxygenation technology [14,15]. However, there is a lack of systematic research on the deoxidation thermodynamics of alloys.…”