Claims
- 1. A fused abrasive grain which is bluish black in color consisting essentially of:
- (1) .[.titanium oxide containing.]. from about 0.42 to about 0.84% titanium, by weight of the abrasive grain, .[.said titanium being present as a reduced titanium oxide having an average oxidation state lower than in Ti.sub.2 O.sub.3 .]. .Iadd.wherein said titanium is present in an easily recognizable second phase and in a form which has a low solubility in aluminum oxide.Iaddend.;
- (2) from about 0.05 to about 0.3% by weight carbon;
- (3) from about 0.02 to about 0.1% by weight Na.sub.2 O;
- (4) from 0 to about 0.1% by weight total of calcium and silicon oxides; and
- (5) alumina; said abrasive .Iadd.grain .Iaddend.having a gain on ignition in air before roasting at 1300.degree. C., when of a size of about 147 microns and finer, of from about 0.4 to about 0.7% by weight .Iadd.and having improved abrasive properties wherein said fused abrasive grain has been roasted by subjecting the grain to an oxidizing atmosphere at a temperature of from about 1250.degree. C. to about 1450.degree. C. for from about 5 minutes to about 64 hours.Iaddend..
- 2. A fused abrasive grain according to claim 1, consisting essentially of:
- (1) .[.titanium oxide containing.]. about 0.72% titanium, by weight of the abrasive grain;
- (2) about 0.2% by weight carbon;
- (3) about 0.05% by weight Na.sub.2 O; and
- (4) about 98.5% by weight alumina; and having a gain on ignition of about 0.5% by weight.
- 3. A coated abrasive product comprising:
- (1) a flexible backing;
- (2) abrasive grain according to claim 1; and
- (3) adhesive bonding said abrasive grain to said backing.
- 4. A coated abrasive product according to claim 3, wherein the flexible backing is cloth; the adhesive comprises a making coat of phenolic resin comprising a calcium carbonate filler and a size coat of phenolic resin comprising a reactive filler.
- 5. A coated abrasive product according to claim 4, comprising a base layer of abrasive grain, under said abrasive grain comprising reduced titanium oxide.
- 6. A bonded abrasive product comprising:
- (1) abrasive grain according to claim 1; and
- (2) a bonding matrix, bonding together the abrasive grain.
- 7. A bonded abrasive product according to claim 6, wherein the bonding matrix is phenolic resin.
- 8. A bonded abrasive product according to claim 6, wherein the bonding matrix is vitrified ceramic bond.
- 9. A bonded abrasive product according to claim 6, in the form of a grinding wheel. .Iadd.
- 10. A fused abrasive grain according to claim 1, wherein the grain size is that produced by solidification of a molten mixture in a water cooled steel pan at a depth of from about 2.5 to about 15 cm. .Iaddend. .Iadd.
- 11. The abrasive grain of claim 1, wherein the grain size is that produced when a molten mixture of the composition set forth is poured into a water cooled steel pan to a depth of from about 2.5 to about 6 cm. .Iaddend. .Iadd.12. The abrasive grain of claim 1, wherein roasting is from about 5 to about 20 minutes. .Iaddend.
Parent Case Info
This is a division of copending application Ser. No. 691,817, filed June 1, 1976 now U.S. Pat. No. 4,111,668.
US Referenced Citations (11)
Foreign Referenced Citations (1)
Number |
Date |
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150116 |
Jun 1919 |
GBX |
Divisions (1)
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Number |
Date |
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Parent |
691817 |
Jun 1976 |
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Reissues (1)
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Number |
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896269 |
Apr 1978 |
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