1.The? Cores? Is? Used? For? Continuous? Casting? Tundish, blooms,? Billets?,? Rectangular? Billet, slab? Steel? Casting ?. 2.To?control?the?molten?steel?flow, for the steelmaking use in the tundish nozzle or the ladle nozzle. 3.It has high corrosion resistence, high tempreture resistence, the zirconia nozzle core can protect the nozzle and the moltensteel well 4.Make the steel more pure, so get the good quality steel, the zirconia nozzle core has long service life.