Authors:
Dr.-Ing. Dániel Veres | TU Bergakademie Freiberg | Germany
Dr.-Ing. Steffen Dudczig | TU Bergakademie Freiberg | Germany
Simon Horn | Chemische Fabrik Budenheim KG | Germany
Kirstin Lippold | Chemische Fabrik Budenheim KG | Germany
Dr. Constanze Setzer | Chemische Fabrik Budenheim KG | Germany
Prof. Dr.-Ing. habil. Christos G. Aneziris | TU Bergakademie Freiberg | Germany
State-of-the-art magnesia-based dry vibrateable tundish linings are predominantly bonded by resin. However, besides high energy consumption, the pyrolysis of the resin-containing lining during the tundish heat-up process generates hazardous gases and carbon residues, resulting in an unwanted carbon pick by molten steel after the finished ladle treatment. For water-based or spray-coated tundish linings, similar energy consumption can be anticipated since the remaining water of the hydraulic bonding need to be removed during the heat-up process to avoid damage of the lining by released steam or H2 dissolution by the steel melt. In contrast, their exist binders with a cold or low-temperature bonding behavior such as sol/gel, acid-base, or thermally (low temperature) activated systems. Hence, the aim of this study was to combine acid-based with thermally activated binders to develop new resin-free tundish linings. Ca-, Na-, and P-containing chemicals/hydrates as well as organic acids were used to promote the thermally activated acid/base bonding reaction. Their influence on the physical and mechanical properties such as density and compressive strength of the lining was investigated. Additionally, utilizing a unique steel casting simulator, the influence of newly developed lining compositions on the steel quality was tested and analyzed. Results showed that the reaction time is strongly dependent from the solubility of the acids. The influence on the inclusion population in molten steel as well as the elemental composition of the steel was evaluated. Newly developed compositions showed no significant influence on the steel cleanliness, only a minor change in the population could be detected.