In connection with the increasing requirements for cleanliness in conticast steel, it is necessary to develop original solutions. The tundish, as the last refractory-lined reactor, gives enough space to remove inclusions by optimizing the flow of steel. The basic component of the tundish is the impact pad, the shape of which creates a suitable flow of steel, thus making it part of the tundish metallurgy. The optimal steel flow in the tundish must avoid creating dead zone areas, or the slag “eye” phenomenon in the slag layer around the ladle shroud, and is intended to create conditions for the release of inclusions by promoting reactions at the steel-slag phase interface. The flow also has to prevent excessive erosion of the tundish refractory lining. This paper compares the standard impact pad with the “Spheric” spherical impact pad using computional fluid dynamiscs (CFD) tools and physical modelling. The evaluation criteria are residence time and flow in the tundish at three different casting speeds.

An alternative binder to calcium aluminate cement (CAC) was prepared by the sol-gel method. Chemically pure systems such as tetraethylorthosilicate (SiC8H20O4) and nonahydrate of alumina nitrate (Al(NO3)3·9H2O) were used as major raw materials. The manufacturing process of binder via solution is mentioned, and transitions in binder structure as a function of thermal treatment in the range between 85 and 1400 °C are described. Finally, binder efficiency was verified by its application in high-temperature concrete instead of calcium aluminate cement (CAC). Newly developed sol-gel binder was characterized by XRFS quantitative analyses, XRD diffraction, STA-DTA and TG analyses and the BET method. Samples of concrete which were based on natural bauxite raw material showed cold compressive strength of 42 MPa compared to the same material where a conventional CAC was applied, and samples reached cold compressive strength of 44 MPa.