Abstract
The effect of Ca treatment on the modification of inclusions in Al-killed GCr18Mo bearing steel was studied and a thermodynamic and kinetic model was established. The experimental results showed that oxygen content in the steel could be reduced from 120 μg/g to the range 5.5–21.6 μg/g by Al-Ca complex deoxidization at 1 873 K. An appropriate increase in Ca/Al mass ratio is beneficial to reduce the total oxygen content in steel. When the content of dissolved aluminum was in the range of 0.03%–0.3%, with the increase of Ca/Al mass ratio from 0.8–1.6 to 2.4–3.2, the number of inclusions per unit area significantly reduced. In addition, the main types of inclusions were modified from large-sized Al2O3 clusters to plastic or semi-plastic liquid phase calcium aluminates. The experimental results matched well with the thermodynamic analysis.
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This study was financially supported by the Shanghai University and the Joint Funds of the National Natural Science Foundation of China (Grant No. U1560202).
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Zheng, HY., Guo, SQ., Qiao, MR. et al. Study on the modification of inclusions by Ca treatment in GCr18Mo bearing steel. Adv. Manuf. 7, 438–447 (2019). https://doi.org/10.1007/s40436-019-00266-1
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DOI: https://doi.org/10.1007/s40436-019-00266-1