Recent development of bearing steel in japan.

Uesugi, Toshikazu

doi:10.2355/isijinternational1966.28.893

Cited by 36 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The composition, size, morphology, quantity, and distribution of inclusions in steel had an important influence on the performance of steel. [ 1–12 ] Various measures were used to control inclusions in steel. [ 13–17 ] During unsteady casting stages such as casting start, ladle exchange, nozzle changing, and casting end, the casting speed changed frequently and the mold level fluctuated greatly, leading to serious slag entrainment and reoxidation of molten steel.…”

Section: Introductionmentioning

confidence: 99%

Evolution of Nonmetallic Inclusions in GCr15 Bearing Steels During Continuous Casting Process

Zhang

Gong²,

Wang

et al. 2021

steel research int.

View full text Add to dashboard Cite

Industrial trials and thermodynamic calculation are carried out to systematically investigate the variation of steel cleanliness and inclusions during the reoxidation of molten steel, steady and unsteady continuous casting process of GCr15 bearing steels. Comparing with inclusions in molten steel, the content of Al2O3, CaO, CaS, and MgO of inclusions in the steady bloom is increased by 2.17%, −18.47%, 14.01%, and 2.27%, respectively, due to the reoxidation of molten steel will inhibit the transformation of inclusions. As the casting length in the first bloom increases from 2 to 9 m, the total oxygen (T.O) content reduced from 12.9 to 7.2 ppm and the number density of inclusions decreases from 15.65 to 10.97 # mm−2 with a gradual decrease in Al2O3 content. Based on thermodynamic consideration, in molten steel, the lower content of T.O, the lower Al2O3 content of inclusions. For solid steel, with the increase in content of T.O, mainly the Al2O3 content of inclusions gradually increases and the CaS content gradually decreases when the T.O content is between 4 and 8 ppm. However, the Al2O3 and CaO content of inclusions gradually increases, then the MgO and CaS contents gradually decreases when the T.O content is between 8 and 25 ppm.

show abstract

Section: Introductionmentioning

confidence: 99%

Evolution of Nonmetallic Inclusions in GCr15 Bearing Steels During Continuous Casting Process

Zhang

Gong²,

Wang

et al. 2021

steel research int.

View full text Add to dashboard Cite

show abstract

“…The demand for the RCF life of bearing steels becomes more stringent, which requires a better control of steel cleanliness. The RCF life of Al-killed bearing steels can be increased 30 times by decreasing the oxygen content from 30 ppm to 5 ppm [6]. Besides, the RCF life is also closely related to the composition of inclusions in bearing steels.…”

Section: Introductionmentioning

confidence: 99%

Transformation of Inclusions in Solid GCr15 Bearing Steels During Heat Treatment

Gong

Zhang

et al. 2019

Metals

View full text Add to dashboard Cite

Laboratory heating experiments with a varied holding time of GCr15 bearing steels at 1498 K were performed to study the transformation of inclusions in solid GCr15 bearing steels during high temperature diffusion processes. Heating experiments at 1573 and 1648 K were also carried out to study the effect of these heating temperatures. Experimental results showed that inclusions transformed from Al2O3-CaO-(MgO) to Al2O3-CaS-(MgO-CaO) when the heat treatment was in the range of 1498 to 1648 K due to reactions between Al and S in the steel matrix and CaO in the inclusions. This is in good agreement with thermodynamic calculations. Moreover, the size of the inclusions hardly changed after heat treatment. The transformation rate of the inclusions depended strongly on both the heating temperature and the size of the inclusions. Kinetic analyses on the transformation of inclusions during heat treatment were performed based on a simplified analytical model. The mass transfer coefficients of CaO and CaS in inclusions were calculated, which ranged from 0.73 × 10−10 to 4.48 × 10−10 m/s.

show abstract

“…For example, both formability and fatigue life are strongly affected by the presence of sulphides and oxides. [10][11][12][13][14][15][16] Inclusion size distribution is important because large macro-inclusions are particularly harmful to mechanical properties. Thus, controlling both the inclusion content and the inclusion size is very important.…”

Section: Introductionmentioning

confidence: 99%

Inclusion characteristics of stainless steel castings

Yin

Yang

Li³

et al. 2016

Ironmaking & Steelmaking

View full text Add to dashboard Cite

The characteristics of non-metallic inclusions in 347 stainless steel samples taken during a netshape casting process after different holding times and melting temperatures were investigated using electrolytic extraction and polished cross-sections. The inclusions can be classified into three groups: oxides, composite inclusions and sulphides. Within the first two groups the inclusions were subdivided based on their morphology into the following categories: spherical, irregular and clusters. As the temperature decreased, sulphide and NbC precipitated within the steel melt as well as on the surface of existing oxides. The number density and area fraction of inclusions as well as the total oxygen contents increased with higher melt temperatures and longer holding times. The results obtained from thermodynamic calculations carried out using the FactSage™ commercial software agreed well with the experimental observations. In addition, it has been concluded that turbulent collisions are the dominant mode for the growth of inclusion clusters.

show abstract

Recent development of bearing steel in japan.

Cited by 36 publications

References 0 publications

Evolution of Nonmetallic Inclusions in GCr15 Bearing Steels During Continuous Casting Process

Evolution of Nonmetallic Inclusions in GCr15 Bearing Steels During Continuous Casting Process

Transformation of Inclusions in Solid GCr15 Bearing Steels During Heat Treatment

Inclusion characteristics of stainless steel castings

Contact Info

Product

Resources

About