Cleanliness of Ti-bearing Al-killed ultra-low-carbon steel during different heating processes

Jian-long Guo; Yan-ping Bao; Min Wang

doi:10.1007/s12613-017-1529-8

Volume 24 Issue 12

Dec. 2017

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Article Navigation > International Journal of Minerals, Metallurgy and Materials > 2017 > 24(12): 1370-1378

Jian-long Guo, Yan-ping Bao, and Min Wang, Cleanliness of Ti-bearing Al-killed ultra-low-carbon steel during different heating processes, Int. J. Miner. Metall. Mater., 24(2017), No. 12, pp. 1370-1378. https://doi.org/10.1007/s12613-017-1529-8

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Jian-long Guo, Yan-ping Bao, and Min Wang, Cleanliness of Ti-bearing Al-killed ultra-low-carbon steel during different heating processes, Int. J. Miner. Metall. Mater., 24(2017), No. 12, pp. 1370-1378. https://doi.org/10.1007/s12613-017-1529-8

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Research ArticleOpen Access

Cleanliness of Ti-bearing Al-killed ultra-low-carbon steel during different heating processes

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Corresponding author:
Yan-ping Bao E-mail: baoyp@ustb.edu.cn
Received: 18 April 2017; Revised: 11 July 2017; Accepted: 16 July 2017

Abstract

Abstract

During the production of Ti-bearing Al-killed ultra-low-carbon (ULC) steel, two different heating processes were used when the converter tapping temperature or the molten steel temperature in the Ruhrstahl-Heraeus (RH) process was low:heating by Al addition during the RH decarburization process and final deoxidation at the end of the RH decarburization process (process-I), and increasing the oxygen content at the end of RH decarburization, heating and final deoxidation by one-time Al addition (process-Ⅱ). Temperature increases of 10℃ by different processes were studied; the results showed that the two heating processes could achieve the same heating effect. The T.[O] content in the slab and the refining process was better controlled by process-I than by process-Ⅱ. Statistical analysis of inclusions showed that the numbers of inclusions in the slab obtained by process-I were substantially less than those in the slab obtained by process-Ⅱ. For process-I, the Al₂O₃ inclusions produced by Al added to induce heating were substantially removed at the end of decarburization. The amounts of inclusions were substantially greater for process-Ⅱ than for process-I at different refining stages because of the higher dissolved oxygen concentration in process-Ⅱ. Industrial test results showed that process-I was more beneficial for improving the cleanliness of molten steel.
- low carbon steel;
- cleanliness;
- RH process;
- heating;
- inclusions

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