As metal raw materials , there is a process of inclusions in liquid steel production will seriously affect the properties of the steel , which restricts the use of steel and, therefore, must take effective measures to remove inclusions in steel , improve the performance of the steel. Removal of fluid inclusions in steel are mainly steel liquid argon technology , mold electromagnetic technology , intermediate packet filtering technology.
1 , Argon Technology
Argon stirring the application of modern steelmaking mature a technology. Its principle is to use a special device to uniform dispersion of inert gas is blown into the molten steel in the form of tiny bubbles, floating bubbles will depend on the interfacial tension mixed particles adsorbed on the surface , floating to the surface removed. In argon technically developed one kind of technology that tundish gas curtain , it was buried in a row ventilation device underwrite , through the micro- bubbles blown into molten steel to form an air curtain wall , collision occurred when the bubble inclusions through and adsorbed on the surface of the bubbles floating for 50-200μm inclusions removed.
2 , mold electromagnetic technology
Mold electromagnetic stirring and electromagnetic technologies, including electromagnetic brake , similar to how they work . Electromagnetic stirring in the mold the slab is disposed rearward linear motion sensor , the moving magnetic fields generated in the drive near Meniscus rotational flow of molten steel in the horizontal direction , to achieve the purpose of stirring . Suitable for inclusion removal of less than 20μm .
Plus one pair of electromagnetic brake is a constant electromagnetic field in the mold of the two wide face , the magnetic field perpendicular to the surface through two wide crystallizer . Liquid steel flows out from the outlet side of the hole , high-speed vertically through the magnetic field , because the steel conductivity , induced current is generated in the electromagnetic field , the liquid steel will be flowing in the opposite direction and their own electromagnetic force , the molten steel flow speed is reduced , reaching braking purposes. The technology was first developed by Sweden and Japan , metallurgy good effect.
3 , intermediate packet filtering technology
Packet filtering technology is to increase the intermediate filter means on the basis of the dam wall , mainly by mechanical removal of the barrier effect of inclusions and surface adsorption . Filter with a microporous structure of the refractories made it across the surface in the middle of two broad package will be completely separated from the tundish , steel only from the pores through . This will not only extend the inclusions in molten steel residence time , and ensures the micro inclusions in molten steel residence time , and ensures the micro inclusions have enough time adsorbed on the filter , to achieve the purpose of removing inclusions . Suitable for all inclusions of particles larger than 20μm .
Applications of existing technology is difficult to completely remove the inclusion of a separate task to complete , so should combine a variety of techniques to seek a more reasonable and feasible method for removing inclusions and technical parameters , to achieve " zero inclusion ."
