The evolution of the inclusion characteristics of GCr15 bearing steel in industrial high basicity refining slag was studied. The number of inclusions with the size larger than 13 µm (Ds inclusions) at the end of ladle furnace refining is 0.3 N/mm2, and the type of inclusions are MgO-Al2O3 and a small amount of CaO-Al2O3-MgO complex inclusions. At the end of RH refining, the number of Ds inclusions is 0.1 N/mm2, and the type of inclusions is CaO-Al2O3 with a high melting point. The inclusions in tundish stage are mainly high melting point CaO-Al2O3 inclusions, in which Ds inclusions disappear and 97% of the inclusions are less than 6 µm. The transition mechanism of inclusions with different [Ca] and [Mg] contents was calculated by thermodynamic FactSage software. The results show that the basicity of refining slag has a great influence on the [Al] content and a little influence on the [Ca] content in molten steel. The [Al] content in molten steel can be increased by increasing the basicity and Al2O3 content of refining slag. This method can inhibit the formation of low melting point CaO-Al2O3 inclusions and reduce the size of inclusions.
LiZKLeiJZXuHF, et al.Current status and development trend of bearing steel in China and abroad. J Iron Steel Res2016; 28: 1.
2.
LiuYZZhouLYZhangCL, et al.Development and quality control of bearing steel for heavy equipment. Iron Steel2013; 48: 1.
3.
GuoDZhangPJiangY, et al.Effects of surface texturing and laminar plasma jet surface hardening on the tribological behaviors of GCr15 bearing steel. Tribol Int2022; 169: 107465.
4.
ZhengXWangBLiuJ, et al.A study of local microstructure decay in GCr15 due to rolling contact. Tribol Int2024; 193: 109419.
5.
HongIJKahramanAAndersonN.A rotating gear test methodology for evaluation of high-cycle tooth bending fatigue lives under fully reversed and fully released loading conditions. Int J Fatigue2020; 133: 105432–105432.11.
6.
SunCLiuXHongY. A two-parameter model to predict fatigue life of high-strength steels in a very high cycle fatigue regime. Acta Mech Sin2015; 31: 383–391.
7.
MurakamiY. Effects of small defects and nonmetallic inclusions on the fatigue strength of metals. Key Eng Mater1991; 51–52: 37–42.
8.
FuruyaYHirukawaHKimuraT, et al.Gigacycle fatigue properties of high-strength steels according to inclusion and ODA sizes. Metall Mat Trans A2007; 38: 1722–1730.
9.
ZhangPLiGZhangJ, et al.Effects of refining slag basicity and vacuum treatment on the cleanliness of bearing steel. Vacuum2024; 222: 112984.
10.
MaWJBaoYPWangM, et al.Influence of slag composition on bearing steel cleanness. Ironmak Steelmak2014; 41: 26–30.
11.
MiaoZChengGLiS, et al.Slag optimization to control CaO increase in inclusions during vacuum degassing of high carbon chromium-bearing steel. Ironmak Steelmak2023; 50: 461–469.
12.
ChunWLHaoZLeiC, et al.Effect of VD low basicity slag on inclusions of GCr15 bearing steel. Special Steel2023; 44: 78.
13.
LiYCLuCLZuoJC, et al.Analysis and control of large inclusions in tunning furnace of bearing steel. Continuous Casting2021; 03: 35–39.
14.
ZengQHuiWZhangY, et al.Very high-cycle fatigue performance of high carbon-chromium bearing steels with different metallurgical qualities. Int J Fatigue2023; 172: 107632.
15.
GuCLianJBaoY, et al.Microstructure-based fatigue modelling with residual stresses: prediction of the fatigue life for various inclusion sizes. Int J Fatigue2019; 129: 105158.
16.
MiaoZChengGLiS, et al.Formation mechanism of large-size CaO-Al2O3-MgO-SiO2 inclusions in high carbon chromium bearing steel. ISIJ Int2021; 61: 2083–2091.
17.
ChenRChenZPXuYT, et al.In-situ observation of behaviors of inclusions in bearing steel. J Iron Steel Res2015; 27: 48–53.
18.
WuHLiQWeiC, et al.Study on the behavior of DS-class inclusions in advanced bearing steel. Metall Res Technol2019; 116: 223.
19.
ZhangHFengGLiuX, et al.Effect of Sulfur content on the composition of inclusions and MnS precipitation behavior in bearing steel. Metals (Basel)2020; 10: 570.
20.
LiMLiSRenY, et al.Modification of inclusions in linepipe steels by Ca-containing ferrosilicon during ladle refining. Ironmak Steelmak2020; 47: 6–12.
21.
BaiSXZengYNNingX, et al.Effect of refining slag composition on steel composition of bearing steel. J North China Univ Sci Technol2023; 45: 114–120.
22.
MouXDYuCShiCM, et al.Formation and controlling of calcium-aluminates inclusions in bearing steel. Chinese J Eng2007; 29: 771–775.
23.
YuHXQuiGYHeLX, et al.Effect of Al2O3 content in refining slag on non-metallic inclusions in Al-killed steel. Steelmaking2023; 39: 18–23.
24.
SongZLiuWLiuY, et al.Optimizing slag content to control Ds-type inclusions in 10B21 cold heading steel. Minerals2021; 11: 1016.
25.
WangYWangKPChenYJ, et al.Evolution of the non-metallic inclusions of bearing steel produced by 90t. Steel Mak2022; 38: 58.
26.
LiXWangLYangS, et al.Effect of slag composition on the cleanliness of drill rod steel. Ironmaking Steelmak2019; 46: 416–423.
27.
KumarDPistoriusPC. Rate of MgO pickup in alumina inclusions in aluminum-killed steel. Metall Mat Trans B2019; 50: 181–191.
28.
ZhaoJXZhuHYWangWS, et al.Interaction between refining slag and high manganese and high aluminum molten steel. J Iron Steel Res2021; 33: 726–733.
29.
TodorokiHMizunoK. Effect of silica in slag on inclusion compositions in 304 stainless steel deoxidized with aluminum. ISIJ Int2004; 44: 1350–1357.
30.
XuJWangKWangY, et al.Influence mechanism of silicon content in Al-killed steel on compositions of inclusions during LF refining. Ironmak Steelmak2021; 48: 127–132.
31.
JiangLPXuJFWangKP, et al.Formation of magnesium-aluminum inclusion in high carbon chromium GCr15 bearing steels and control process practice. Special Steel2022; 43: 41.
32.
DengZLiuZZhuM, et al.Formation, evolution and removal of MgO-Al2O3 spinel inclusions in steel. ISIJ Int2021; 61: 1–15.
33.
WangKPWangYXieW, et al.Influence of RH vacuum treatment on spinel inclusions of high carbon chromium bearing steel. Iron Steel2023; 58: 108–115.
34.
KangYJLiFMoritaK, et al.Mechanism study on the formation of liquid calcium aluminate inclusion from MgO-Al2O3 spinel. Steel Res Int2006; 77: 785–792.
35.
XingLBaoYWangM. Evolution of inclusions in the whole process of GCr15 bearing steels. Metall Res Technol2023; 120: 301.
36.
ChiYGDengZYZhuMY. Effects of refractory and ladle glaze on evolution of non-metallic inclusions in Al-killed steel. Steel Res Int2017; 88: 1600470.
37.
KongLDengZZhuM. Formation and evolution of non-metallic inclusions in medium Mn steel during secondary refining process. ISIJ Int2017; 57: 1537–1545.
