阅读说明：本技术 耐火过滤器 (Fire-resistant filter ) 是由 戴维·贝尔 于 2020-10-29 设计创作，主要内容包括：一种适用于过滤熔融金属如钢水的耐火过滤器,以及用于生产所述过滤器的方法和粉状组合物。所述过滤器包括耐火材料,所述耐火材料包含：60-90重量％的氧化铝；8-30重量％的氧化锆；和3-20重量％的氧化镁。所述粉状组合物包含：60-90重量％的氧化铝；8-30重量％的氧化锆；和3-20重量％的氧化镁,其中所述粉状组合物包含小于12.5重量％的活性氧化铝、煅烧氧化铝或其混合物,并且其中剩余的氧化铝是片状氧化铝。所述方法包括：提供根据本发明的粉状组合物；由该粉状组合物和液体组分形成过滤器前体；和烧制该过滤器前体以形成耐火过滤器。(A refractory filter suitable for filtering molten metal, such as molten steel, and a method and powdered composition for producing the filter. The filter includes a refractory material comprising: 60-90% by weight of alumina; 8-30% by weight of zirconia; and 3-20 wt% magnesium oxide. The powdered composition comprises: 60-90% by weight of alumina; 8-30% by weight of zirconia; and 3-20 wt.% magnesium oxide, wherein the powdered composition comprises less than 12.5 wt.% of activated alumina, calcined alumina, or a mixture thereof, and wherein the remaining alumina is tabular alumina. The method comprises the following steps: providing a powdered composition according to the present invention; forming a filter precursor from the powdered composition and the liquid component; and firing the filter precursor to form the refractory filter.)

1. A refractory filter for filtering molten steel, the refractory filter comprising a refractory material comprising: 60-90% by weight of alumina; 8-30% by weight of zirconia; and 3-20 wt% magnesium oxide.

2. The refractory filter of claim 1, wherein the refractory material is substantially free of silica.

3. The refractory filter of claim 1 or claim 2, wherein the refractory filter has a compressive strength of at least 4 MPa.

4. The refractory filter according to any one of the preceding claims, wherein the refractory filter has at least one first surface forming a side of the filter and two opposing second surfaces forming a flow surface of the filter, the second surfaces having no more than 500cm²The area of (a).

5. The refractory filter according to any one of the preceding claims, wherein the filter is framed.

6. The fire resistant filter of any one of the preceding claims, wherein the fire resistant filter is a foam filter, a honeycomb filter, or a pressed filter.

7. The refractory filter according to any one of the preceding claims, wherein the refractory material further comprises up to 5 wt% titania.

8. The refractory filter of any one of the preceding claims, wherein the refractory material is prepared using less than 12.5 wt.% activated or calcined alumina.

9. A powdered composition for use in the manufacture of a refractory filter, the powdered composition comprising 60 to 90 wt% alumina; 8-30% by weight of zirconia; and 3-20 wt.% magnesium oxide, wherein the powdered composition comprises less than 12.5 wt.% of activated alumina, calcined alumina, or a mixture thereof, and wherein the remaining alumina is plate alumina.

10. The powdered composition according to claim 9, wherein the powdered composition comprises 0 to 10 wt.% of activated alumina, calcined alumina, or a mixture thereof.

11. The powdered composition according to claim 9 or claim 10, wherein the powdered composition comprises at least 60 wt.% tabular alumina.

12. The powder composition according to any one of claims 9 to 11, wherein the tabular alumina has a D50 particle size of less than 500 μ ι η.

13. The powdered composition of any one of claims 9 to 11 wherein the tabular alumina comprises a mixture of finer tabular alumina having a D50 particle size of 20 to 50 μ ι η and coarser tabular alumina having a D50 particle size of 100 to 500 μ ι η.

14. A pulverulent composition according to claim 13, wherein the ratio of finer flake alumina to coarser flake alumina is from 40: 60 to 60: 40.

15. The powder composition of any one of claims 9 to 14, wherein the activated alumina, when present, has a D50 particle size of less than 10 μ ι η.

16. The powder composition of any one of claims 9 to 15, wherein the magnesium oxide has a D50 particle size of less than 30 μ ι η.

17. The powder composition of any one of claims 9-16, wherein the zirconia has a D50 particle size of less than 1 μ ι η.

18. The powder composition of any one of claims 9-17, wherein the powder composition comprises less than 1 wt% silica.

19. The powdered composition of claim 18, wherein the powdered composition is substantially free of silica.

20. The powdered component according to any one of claims 9 to 19, wherein the magnesium oxide is at least partially replaced by cerium oxide.

21. The powdered composition according to any one of claims 9 to 20, further comprising up to 5 wt% titanium dioxide.

22. Use of the powdered composition according to any one of claims 9 to 21 for forming a refractory filter.

23. A method for producing a refractory filter, the method comprising:

providing a powdered composition according to any one of claims 9 to 21;

forming a filter precursor from the powdered composition and a liquid component; and

firing the filter precursor to form a refractory filter.

24. The method of claim 23, wherein the filter precursor is dried prior to firing.

25. The method of claim 23 or claim 24, wherein forming the filter precursor comprises 3D printing.

26. The method of claim 23 or claim 24, wherein forming the filter precursor comprises:

combining the powdered composition and the liquid component to form a slurry, and

impregnating a reticulated foam substrate with the slurry to form the filter precursor.

27. The method of claim 26, wherein the reticulated foam substrate is impregnated with the slurry by spraying, roll dipping, dip coating, centrifuging, or any combination thereof.

28. The method of any one of claims 23 to 27, wherein the filter precursor is fired at a temperature greater than 1500 ℃.

29. The method of any one of claims 23 to 28, wherein the filter precursor is fired for at least 30 minutes.

30. The method of any one of claims 23 to 29, wherein the filter precursor is fired in an oxidizing atmosphere.