Recent advancements in the production of 9Ni steel have showcased a significant evolution in inclusion treatment optimization, promising to enhance the quality and performance of steel used in construction. A team of researchers, led by Chen Dengguo and his colleagues from Xinyu Iron and Steel Co., Ltd., and Anhui University of Technology, conducted a detailed study published in ‘Teshugang’ that delves into the intricacies of inclusion dynamics during the steelmaking process.
The research utilized industrial testing alongside Aspex automatic inclusion analysis technology to systematically investigate the behavior of total oxygen (T.O) and nitrogen (N) content, as well as the characteristics of microinclusions in 9Ni steel throughout the LF (Ladle Furnace), RH (Vacuum Degassing), and CC (Continuous Casting) processes. The findings revealed a notable increase in T.O and N content during specific intervals, indicating instances of secondary oxidation within the molten steel. “Understanding these oxidation processes is crucial for improving the purity and overall quality of steel,” Chen noted, highlighting the commercial implications of their findings for the construction sector.
One of the pivotal outcomes of this research was the identification of the primary inclusions present in 9Ni steel, which were found to be complex combinations of CaO-Al2O3-MgO and CaO-Al2O3-CaS. The study also examined the effects of calcium treatment on the size and density of these inclusions. Remarkably, when the calcium line was reduced from 200 meters to 100 meters, the density of inclusions measuring between 2 μm and 5 μm significantly decreased, effectively eliminating inclusions containing CaS. This reduction in inclusion grades from 1.0 and 1.5 to 0.5 for DT and DS inclusions, respectively, suggests a substantial improvement in the steel’s quality.
The implications of these developments extend beyond the laboratory and into the construction industry. High-quality steel with fewer inclusions not only enhances structural integrity but also improves durability and longevity, which are critical factors in construction projects. As Chen emphasized, “These results pave the way for producing cleaner steel, which is essential for meeting the rigorous standards of modern construction.”
This research not only provides valuable insights into the steelmaking process but also sets the stage for future innovations in steel production techniques. By leveraging advanced technologies like Factsage software for inclusion formation analysis, manufacturers can optimize their processes to produce steel that meets the evolving demands of the construction sector.
For further insights into this research, interested readers can visit Xinyu Iron and Steel Co., Ltd., where the lead authors continue to explore the intersections of metallurgy and construction. The findings are detailed in the recent publication in ‘Teshugang,’ also known as ‘Steelmaking.’ As the construction industry pushes towards higher standards, studies like this one will play a crucial role in shaping the future of steel production.
