Fire-resistant ceramic mix and fire resistant ceramic product

Patent metadata

Field	Value
Publication number	US-9656919-B2
Application number	US-201414778472-A
Country	US
Kind code	B2
Filing date	Jan 20, 2014
Priority date	Mar 22, 2013
Publication date	May 23, 2017
Grant date	May 23, 2017

Abstract

The invention concerns a refractory ceramic batch as well as a refractory ceramic product.

First claim

The invention claimed is:

1. A refractory ceramic batch based on magnesia, having the following characteristics:
1 the batch comprising:
1.1.1 at least 70% by weight of magnesia,
1.1.2 at least one plasticizer
wherein the at least one plasticizer comprises at least one of magnesia spinel, hercynite, galaxite or jacobsite, as well as

1.1.3 at least one phosphorus-comprising component;

1.2 wherein the batch comprises proportions of CaO and SiO 2
wherein the mole fraction of CaO in the batch is more than twice the mole fraction of SiO 2 in the batch.

2. The batch as claimed in claim 1 , in which the proportion by weight of phosphorus in the batch, calculated as P 2 O 5 , is at most 50% above or below the value for the fraction by weight of P 2 O 5 , calculated in accordance with the following formula (I):

P
2

⁢

O

5
⁢

⁢
ideal

⁢

[

weight
⁢

⁢
%

]

=

(

CaO
free

)

·

b
a

(
I
)

wherein said percentage of at most 50% is with respect to said value and wherein CaO free is the quantity of free CaO in the batch as a weight %, which is determined using the following formula:

CaO
free

=

x
-

2
·
y
·
c

s

(
II
)

with
x=proportion of CaO in batch [weight %]
y=SiO 2 content in batch [weight %]
c=molecular weight of CaO [g/mol]=56 g/mol
s=molecular weight of SiO 2 [g/mol]=60.1 g/mol
a=fraction of CaO in tricalcium phosphate [weight %]=54.2%, and
b=fraction of P 2 O 5 in tricalcium phosphate [weight %]=45.8%.

3. The batch as claimed in claim 1 , in which the phosphorus comprising component is present in such fractions by weight in the batch that phosphorus, calculated as P 2 O 5 , is present in the batch in the range from 0.1% to 5%, with respect to the total weight of the batch.

4. The batch as claimed in claim 2 , in which the fraction by weight of CaO is in the range 0.2% to 8% by weight with respect to the total weight of the batch.

5. The batch as claimed in claim 2 , in which the fraction by weight of SiO 2 is in the range 0.05% to 3% by weight with respect to the total weight of the batch.

6. The batch as claimed in claim 1 , in which the fraction by weight of Fe 2 O 3 which is not present in the batch in the form of a plasticizer is more than 3% by weight with respect to the total weight of the batch.

7. The batch as claimed in claim 1 , in which the fraction by weight of magnesia is in the range 70% to 97% by weight with respect to the total weight of the batch.

8. The batch as claimed in claim 1 , in which the fraction by weight of plasticizer is in the range 2% to 30% by weight with respect to the total weight of the batch.

9. A shaped refractory ceramic product which is produced from a batch as claimed in claim 1 by ceramic firing and which comprises the following phases:
magnesia,
at least one mineral phase which has been formed from at least one plasticizer, as well as
at least one of the following phases: tricalcium phosphate or a calcium-silicate-phosphate solid solution.

10. The product as claimed in claim 9 , in which the fraction by weight of tricalcium phosphate is in the range 0.5% to 6% by weight with respect to the total weight of the product.

11. The product as claimed in claim 9 , in which the fraction by weight of calcium-silicate-phosphate solid solution is in the range 0.5% to 8% by weight with respect to the total weight of the product.

12. The product as claimed in claim 9 , having a T 0 value of more than 1,325° C.

13. The product as claimed in claim 9 , having at least one of the following properties:
modulus of elasticity: <70 GPa, <60 GPa, <50 GPa or <40 GPa,
nominal notched-bar tensile strength: <10 MPa, <9 MPa, <8 MPa or <7 MPa.

14. The batch as claimed in claim 2 , in which the phosphorus comprising component is present in such fractions by weight in the batch that phosphorus, calculated as P 2 O 5 , is present in the batch in the range from 0.1% to 5%, with respect to the total weight of the batch.

15. The batch as claimed in claim 1 , in which the fraction by weight of CaO is in the range 0.2% to 8% by weight with respect to the total weight of the batch.

16. The batch as claimed in claim 1 , in which the fraction by weight of SiO 2 is in the range 0.05% to 3% by weight with respect to the total weight of the batch.

17. The batch as claimed in claim 2 , in which the fraction by weight of Fe 2 O 3 which is not present in the batch in the form of a plasticizer is more than 3% by weight with respect to the total weight of the batch.

18. The batch as claimed in claim 2 , in which the
fraction by weight of magnesia is in the range 70% to 97% by weight with respect to the total weight of the batch.

19. The batch as claimed in claim 2 , in which the fraction by weight of plasticizer is in the range 2% to 30% by weight with respect to the total weight of the batch.

20. A shaped refractory ceramic product which is produced from a batch as claimed in claim 2 by ceramic firing and which comprises the following phases:
magnesia,
at least o

Assignees

• Refractory Intellectual Property Gmbh & Co Kg

Inventors

• Gelbmann Gerald
• Kahr Friedrich

Classifications

• C04B2235/3272

  Iron oxides or oxide forming salts thereof, e.g. hematite, magnetite · CPC title

• C04B2235/447

  Phosphates or phosphites, e.g. orthophosphate or hypophosphite · CPC title

• C04B35/66

  Monolithic refractories or refractory mortars, including those whether or not containing clay {(making or repairing of linings F27D1/16)} · CPC title

• C04B2235/3208

  Calcium oxide or oxide-forming salts thereof, e.g. lime · CPC title

• C04B2235/3418

  Silicon oxide, silicic acids or oxide forming salts thereof, e.g. silica sol, fused silica, silica fume, cristobalite, quartz or flint · CPC title