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 semiplastic liquid phase calcium aluminates. The experimental results matched well with the thermodynamic analysis.
The full text can be downloaded at https://link.springer.com/article/10.1007/s40436-019-00266-1
Hong-Yan Zheng
,
Shu-Qiang Guo
,
Meng-Ran Qiao
,
Li-Bin Qin
,
Xiu-Jing Zou
,
Zhong-Ming Ren
. Study on the modification of inclusions by Ca treatment in GCr18Mo bearing steel[J]. Advances in Manufacturing, 2019
, 7(4)
: 438
-447
.
DOI: 10.1007/s40436-019-00266-1
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