Refractory product, use of zirconium dioxide, zirconium dioxide, method for manufacturing a refractory product and a refractory product manufactured therewith

1. A refractory product comprising a mineral phase in the form of zirconium dioxide in the cubic variant thereof that is metastable at room temperature, having a content of calcium, magnesium and yttrium less than 1% by weight, wherein the zirconium dioxide comprises monocrystallites with a grain size in the range from 30 to 1,000 μm and wherein the quantity of oxides in the zirconium dioxide other than ZrO 2 or HfO 2 is less than 1.5% by weight.

2. The product according to claim 1 , in the shape of a wearing part for continuous steel casting.

3. The product according to claim 1 , in the shape of a slide plate, a monobloc stopper, a nozzle, an immersion pipe or a submerged nozzle.

4. The product according to claim 1 , in which the zirconium dioxide is present in a carbon matrix.

5. The product according to claim 1 , in which the zirconium dioxide was obtained by firing zirconium dioxide that was partly or fully stabilised with stabilising additives in a reducing atmosphere and in the presence of a gas-phase reagent for the stabilising additives, followed by cooling.

6. The product according to claim 5 , with stabilising additives in the form of at least one of the following substances: calcium oxide, magnesium oxide, yttrium oxide, or rare earth oxides.

7. The product according to claim 5 , in which the reducing atmosphere has a partial oxygen pressure below 10-6 Pa.

8. The product according to claim 5 , with a gas-phase reagent in the form of at least one of the following gas-phase substances: silicon, aluminium or carbon monoxide.

9. The product according to claim 5 , in which the firing is carried out at temperatures in the range from 1,173 to 2,690° C.

10. A zirconium dioxide in the form of a mineral phase that is metastable in the cubic variant thereof at room temperature, with a content of less than 1% by weight calcium, magnesium and yttrium, wherein the zirconium dioxide comprises monocrystallites with a grain size in the range from 30 to 1,000 μm and wherein the quantity of oxides in the zirconium dioxide other than ZrO 2 or HfO 2 is less than 1.5% by weight.

11. A method for manufacturing a refractory product comprising the following steps:

providing a mineral phase that is metastable at room temperature in the form of zirconium dioxide in the cubic variant containing a quantity of less than 1% by weight calcium, magnesium and yttrium, wherein the zirconium dioxide comprises monocrystallites with a grain size in the range from 30 to 1,000 μm and wherein the quantity of oxides in the zirconium dioxide other than ZrO 2 or HfO 2 is less than 1.5% by weight;

combining the zirconium dioxide with additional refractory raw materials;

pressing a moulded body made from the zirconium dioxide and the additional refractory raw materials;

firing the moulded body to produce a refractory product.

12. A refractory product manufactured using a method, the method comprising:

providing a mineral phase that is metastable at room temperature in the form of zirconium dioxide in the cubic variant containing a quantity of less than 1% by weight calcium, magnesium and yttrium, wherein the zirconium dioxide comprises monocrystallites with a grain size in the range from 30 to 1,000 μm and wherein the quantity of oxides in the zirconium dioxide other than ZrO 2 or HfO 2 is less than 1.5% by weight;

combining the zirconium dioxide with additional refractory raw materials;

pressing a moulded body made from the zirconium dioxide and the additional refractory raw materials; and

firing the moulded body to produce a refractory product.