Molten alumina-zirconia grains

Patent metadata

Field	Value
Publication number	US-11072563-B2
Application number	US-201716075781-A
Country	US
Kind code	B2
Filing date	Feb 10, 2017
Priority date	Feb 12, 2016
Publication date	Jul 27, 2021
Grant date	Jul 27, 2021

Abstract

A fused grain having the following chemical composition in percent by weight in relation to the oxides: ZrO 2 : 16% to 30%, provided that HfO 2 <2%, Al 2 O 3 : percentage needed to bring the total to 100%, Cr 2 O 3 : ≥0.2%, TiO 2 : ≥0.5%, Cr 2 O 3 +TiO 2 : <7%, other elements: <3%, provided that SiO 2 +CaO+MgO<1.5%.

First claim

The invention claimed is:

1. A fused grain exhibiting the following chemical analysis, as percentages by weight based on the oxides:
ZrO 2 : 16% to 30%, provided that HfO 2 <2%,
Al 2 O 3 : remainder to 100%,
Cr 2 O 3 : ≥0.2% and ≤4%,
TiO 2 : ≥0.5%,
Cr 2 O 3 +TiO 2 : <7%,
Other elements: <3%, provided that SiO 2 +CaO+MgO<1.5%.

2. The grain as claimed in claim 1 , in which Cr 2 O 3 >0.4%.

3. The grain as claimed in claim 1 , in which
the TiO 2 content is less than or equal to 6%,
as percentages by weight based on the oxides.

4. The grain as claimed in claim 1 ,
in which the ZrO 2 content is greater than 18%, and/or
in which the Cr 2 O 3 content is greater than 0.5%, and/or
in which the TiO 2 content is greater than 0.8%,
as percentages by weight based on the oxides.

5. The grain as claimed in claim 4 ,
in which the ZrO 2 content is greater than 20%, and/or
in which the TiO 2 content is greater than 1%,
as percentages by weight based on the oxides.

6. The grain as claimed in claim 1 ,
in which the ZrO 2 content is less than 29%, and/or
in which the Cr 2 O 3 content is less than 3.2%, and/or
in which the TiO 2 content is less than 4.4%,
as percentages by weight based on the oxides.

7. The grain as claimed claim 6 ,
in which the ZrO 2 content is less than 27%, and/or
in which the Cr 2 O 3 content is less than 2.2%, and/or
in which the TiO 2 content is less than 2.8%,
as percentages by weight based on the oxides.

8. The grain as claimed in claim 1 , in which the Cr 2 O 3 +TiO 2 summed content is greater than 1.5% and less than 3.3%, as percentages by weight based on the oxides.

9. The grain as claimed in claim 1 ,
in which the TiO 2 content is greater than 4% and less than 6.5%, and
in which the Cr 2 O 3 +TiO 2 summed content is greater than 4.4% and preferably less than 6.9%,
as percentages by weight based on the oxides.

10. The grain as claimed in claim 1 , in which the content of other elements is less than 2%, as percentages by weight based on the oxides.

11. The grain as claimed in claim 1 , in which the SiO 2 +CaO+MgO content is less than 1%.

12. The grain as claimed in claim 1 , in which
the SiO 2 content is less than 1%, and/or
the MgO content is less than 0.5%, and/or
the CaO content is less than 0.5%, and/or
the Na 2 O content is less than 0.1%,
as percentages by weight based on the oxides.

13. The grain as claimed in claim 12 , in which
the SiO 2 content is less than 0.8%, and/or
the MgO content is less than 0.3%, and/or
the CaO content is less than 0.3%, and/or
the Na 2 O content is less than 0.05%,
as percentages by weight based on the oxides.

14. A mixture of grains comprising, as percentages by weight, more than 80% of abrasive grains as claimed in claim 1 .

15. An abrasive tool comprising grains bound by a binder, bonded or deposited on a support, at least a portion of said grains being in accordance with claim 1 .

16. The abrasive tool as claimed in claim 15 , wherein said at least a portion of said grains comprising more than 80% of said grains.

17. The abrasive tool as claimed in claim 15 , which is provided in the form of a grinding wheel.

18. The grain as claimed in claim 10 , in which the content of other elements is less than 1%, as percentages by weight based on the oxides.

19. The grain as claimed in claim 11 , in which the SiO 2 +CaO+MgO content is less than 0.8%.

20. A fused grain exhibiting the following chemical analysis, as percentages by weight based on the oxides:
ZrO 2 : 16% to 30%, provided that HfO 2 <2%,
Al 2 O 3 : remainder to 100%,
Cr 2 O 3 : ≥0.2%,
TiO 2 : ≥0.5%,
Cr 2 O 3 +TiO 2 : <5.2%,
Other elements: <3%, provided that SiO 2 +CaO+MgO<1.5%.

21. The grain as claimed in claim 20 , in which Cr 2 O 3 +TiO 2 <4%.

22. The grain as claimed in claim 20 , in which Cr 2 O 3 +TiO 2 <3.3%.

23. A fused grain exhibiting the following chemical analysis, as percentages by weight based on the oxides:
ZrO 2 : 16% to 30%, provided that HfO 2 <2%,
Al 2 O 3 : remainder to 100%,
Cr 2 O 3 : ≥0.2%.
TiO 2 : ≥4%,
Cr 2 O 3 +TiO 2 : <7%,
Other elements: <3%, provided that SiO 2 +CaO+MgO <1.5%.

24. The grain as claimed in claim 23 , in which TiO 2 <6.5%.

Assignees

• Saint Gobain Ct Recherches

Inventors

• Delwaulle Céline
• Apheceixborde Arnaud

Classifications

• C04B2235/3206

  Magnesium oxides or oxide-forming salts thereof · CPC title

• C04B2235/3232

  Titanium oxides or titanates, e.g. rutile or anatase · CPC title

• C04B35/109 Primary

  containing zirconium oxide or zircon (ZrSiO4) · CPC title

• C09K3/1427

  obtained by division of a mass agglomerated by melting, at least partially, e.g. with a binder · CPC title

• C04B2235/3201

  Alkali metal oxides or oxide-forming salts thereof · CPC title