The optimization of the aluminum deoxidation process to reduce non-metallic inclusions in steel products

Document Type : Research Paper


Department of Research and Development, Iran Alloy Steel Company, Yazd, Iran



Nowadays, clean liquid steel is crucial for improving castability, increasing production efficiency, and generating high-quality, customer-satisfying products. This research studied the influence of aluminum deoxidation process on the inclusion content in steel products. The image analysis technique and the calculation of inclusion volume fraction were used to assess the cleanliness of steel products. A total of 37 heats of typical medium carbon Al killed steel with aluminum contents in the 0.015-0.040 wt.% range were put to the test. The findings revealed that at least 70% of the total aluminum utilized in the tapping and ladle furnace (LF) must be added during the tapping process in order to produce a clean steel product with an inclusion volume fraction of less than 0.023%. Moreover, aluminum granules need to be added once throughout the LF process during the first 15 minutes of the process. In order to adjust the aluminum content in the liquid steel, the aluminum wire must be fed all at once at the last minute of the LF process.


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