Patent EP0441640A2 successfully refreshed from Google Patents.
EP0441640A2
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Sintered aluminous abrasive grains and method of producing the same
Assignee: Japan Abrasive Co Ltd
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Filing: 1991-02-08
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Granted: —
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Expires: 2011-02-08
Abstract
Abstract Sintered aluminous abrasive grains having a density of at least 95% of theoretical density and having an alpha alumina crystal size of smaller than one micron, whi are obtained by drying and crushing a lithium containing alumina dispersion and sintering the crushed objects at 1100-1500 DEG C, said abrasive grains have the strength and hardness equal to or higher than conventional abrasive grains, superior properties in grinding resistance and wear resistance and superiro self-sharpening property in course of grinding.
Inventors
- 👤 Masahiro Tamamaki
- 👤 Yoshihiro Onoda
- 👤 Masaru Nozaki
- 👤 Naruo Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 06:40
CPC Classifications
C; C09; C09K; C09K3/00; C09K3/14; C09K3/1409; C09K3/1418; C04; C04B; C04B35/00; C04B35/01; C04B35/10; C04B35/111; C04B35/1115
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
45 words
Sintered aluminous abrasive grains containing an aluminium oxide having the purity of higher than 98.0 wt% and a lithium oxide of 0.01-1.5 wt%, having a density of at least 95% of theoretical density and having an alpha alumina crystal size of smaller than one micron.
Claim 2
Dependent Claim
15 words
Sintered aluminous abrasive grains claimed in Claim 1, wherein alpha alumina crystallization ratio is 75-95%.
Claim 3
Dependent Claim
26 words
Sintered aluminous abrasive grains claimed in Claim 1 or claim 2, wherein lithium oxide content is 0.03-1.5 wt% and alpha alumina crystal size is 0.1-0.5 microns.
Claim 4
Dependent Claim
37 words
Method of producing sintered aluminous abrasive grains comprising providing a dispersion comprising water , alumina monohydrate, lithium precursor and acid, drying and crushing said lithium containing dispersion and sintering the crushed objects at a temperature of 1100-1500°C.
Claim 5
Dependent Claim
21 words
Method of producing sintered aluminous abrasive grains claimed in Claim 4, wherein alumina modifying components are added in the dispersion .
Claim 6
Dependent Claim
21 words
Method of producing sintered aluminous abrasive grains claimed in Claim 4 or claim 5, wherein the dispersion is prepared at 40-80°C.
Claim 7
Dependent Claim
27 words
Method of producing sintered aluminous abrasive grains claimed in any one of Claims 4 to 6, wherein the dispersion is further subjected to a ultrasonic vibration treatment.
Claim 8
Dependent Claim
29 words
Method of producing sintered aluminous abrasive grains claimed in any one of Claims 4 to 7, wherein acid is nitric acid, hydrocloric acid, acetic acid or mixed acid thereof.
Claim 9
Dependent Claim
41 words
Method of producing sintered aluminous abrasive grains claimed in Claim 5, or in any claim dependent upon claim 5, wherein said modifying component is selected from the group of Mg, Ca, Co, Ni, Cr, Fe, Si, Zn, Mn, Ti and Zr.
Claim 10
Dependent Claim
25 words
Grinding wheels containing the sintered aluminous abrasive grains claimed in any one of Claims 1 to 3 and sintered with an inorganic or organic bond.
Claim 11
Dependent Claim
24 words
Coated abrasive articles containing the sintered aluminous abrasive grains claimed in any one of Claims 1 to 3 and sintered with an resinoid bond.
References Cited (Backward Citations)
No citation records indexed.
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