Cerium Addition Improves Cleanliness and Refines Microstructure of As‐Cast High‐Nitrogen Stainless Bearing Steel

High‐nitrogen stainless bearing steel (HNSBS) is the most representative third‐generation aviation bearing steel, and the cleanliness and microstructure characteristics of bearing steel are crucial to its high performance and long service life. In this work, the effect of cerium addition on the clea...

Full description

Saved in:
Bibliographic Details
Published in:Steel research international 2024-03, Vol.95 (3), p.n/a
Main Authors: Lu, Peng‐Chong, Feng, Hao, Li, Hua‐Bing, Zhang, Peng‐Fei, Zhu, Hong‐Chun, Zhang, Shu‐Cai, Jiang, Zhou‐Hua
Format: Article
Language:English
Subjects:
Alloy systems
Aluminum oxide
Bearing steels
Cerium
cerium addition
Cleanliness
cleanliness improvement
Dendritic structure
high‐nitrogen stainless bearings steel
inclusion evolution
Inclusions
Liquid phases
Microstructure
microstructure characterization
Nitrogen
Nucleation
precipitate types
Precipitates
Service life
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:High‐nitrogen stainless bearing steel (HNSBS) is the most representative third‐generation aviation bearing steel, and the cleanliness and microstructure characteristics of bearing steel are crucial to its high performance and long service life. In this work, the effect of cerium addition on the cleanliness and microstructure characteristics of as‐cast HNSBS was systematically studied by combining microstructural characterization and thermodynamic analysis methods. The results show that with increasing Ce content, the cleanliness of steel first improved and then decreased, and Ce2O2S, Ce2O3 and CeN inclusions were generated successively. The Ce content should be controlled to ≈0.012 wt% to ensure that all Al2O3, MgO · Al2O3, and MnS inclusions were modified, and minimize the formation of large‐size Ce‐bearing inclusions. Furthermore, cerium addition refined the dendrite structure due to more nucleation sites for γ‐Fe and the enrichment of Ce in the liquid phase at solidifying front. The finer and more dispersed distribution in precipitates was ascribed to the reduction of growth space and Cr segregation, as well as the increase in effective nucleation sites. These results can offer theoretical guidance for inhibiting the formation of harmful inclusions in high‐nitrogen alloy systems and refining the microstructure of alloy systems containing M23(C, N)6 and M2(C, N) precipitates. This work systematically investigated the effect of cerium addition on cleanliness and microstructure characteristics of as‐cast HNSBS, which could offer theoretical guidance for inhibiting the formation of deleterious inclusions in high‐nitrogen alloy systems and refining the microstructure of alloy systems containing M23(C, N)6 and M2(C, N) precipitates.
ISSN:1611-3683
1869-344X
DOI:10.1002/srin.202300648