US3841852A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Abraders, abrasive particles and methods for producing same
Assignee: Norton Christensen Inc
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Filing: 1972-01-24
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Granted: 1974-10-15
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Expires: 1992-01-24
Abstract
Abstract Abraders are formed from encapsulated abrasive particles which are uniformly distributed in a matrix. Superior abraders may be formed by metal bonding such encapsulated abrasives with a metal matrix which forms a continuous phase in which the abrasive particles may be positioned. Where the abrader is formed from a mixture of the bonding metal and a single type of abrasive particle, the specific gravity of the abrasive particle may be adjusted to match more closely that of the metal. The encapsulated abrasive particle may form the primary abrasive together with a secondary abrasive which is not as hard as the primary abrasive and which may or may not be encapsulated with a metal. Where a plurality of abrasive particles of differing specific gravity are used, one or the other or both may be adjusted in density by employing an encapsulating metal of suitable specific gravity. Abrasive particles are improved in function as abrasives, in addition to having the specific gravity adjusted by encapsulating them with a metallic envelope; preferably the envelope is made of a pure metal in dendritic crystalline form. Desirably the abrasive substrate is placed in contraction by the envelope which is heat shrunk onto the abrasive substrate. The preferred method is to deposit the metal on the substrate at an elevated temperature by contacting a vapor of the metallic compound with the substrate particle under reducing conditions. The preferred primary abrasive is a diamond, and it is preferably etched before coating.
Inventors
- 👤 A Wilder
- 👤 H Bridwell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 05:31
CPC Classifications
C; C09; C09K; C09K3/00; C09K3/14; C09K3/1436; C09K3/1445; B; B24; B24D; B24D3/00; B24D3/02; B24D3/04; B24D3/06; B24D3/08; B24D7/00
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
121 words
A SHAPED ABRADER COMPRISING A CONTINUOUS PHASE OF A METAL MATRIX, PRIMARY ABRASIVE PARTICLES AND SECONDARY ABRASIVE PARTICLES, SAID PRIMARY AND SECONDARY ABRASIVE PARTICLES BEING OF DIFFERENT DENSITIES, THE PRIMARY ABRASIVE PARTICLES HAVING A HARDNESS MORE THAN 2,000 KG/MM2, AND SAID SECONDARY ABRASIVE PARTICLES HAVING A HARDNESS OF ABOVE ABOUT 1,250 KG/MM2 AND LESS THAN THE HARDNESS OF THE PRIMARY ABRASIVE PARTICLES, THE PARTICLES OF LOWER DENTISY, BEING ENCAPSULATED IN A METAL ENVELOPE, THE DENSITIES OF SAID ENCAPSULATED PARTICLES OF LOWER DENSITY BEING GREATER THAN THE DENSITY OF THE UNENCAPSULATED PARTICLES OF LOWER DENSITY, SAID ENCAPSULATED PARTICLES HAVIG A DENSITY MORE THAN 30 PERCENT OF THE DENSITY OF HIGHEST DENSITY, AND SAID PARTICLES BEING SUBSTANTIALLY UNIFORMLY DISTRIBUTED IN SAID METAL MATRIX.
Claim 2
Dependent Claim
121 words
A SHAPED ABRADER COMPRISING A CONTINUOUS PHASE OF A METAL MATRIX, PRIMARY ABRASIVE PARTICLES AND SECONDARY ABRASIVE PARTICLES, SAID PRIMARY AND SECONDARY ABRASIVE PARTICLES BEING OF DIFFERENT DENSITIES, THE PRIMARY ABRASIVE PARTICLES HAVING A HARDNESS MORE THAN 2,000 KG/MM2, AND SAID SECONDARY ABRASIVE PARTICLES HAVING A HARDNESS OF ABOVE ABOUT 1,250 KG/MM2 AND LESS THAN THE HARDNESS OF THE PRIMARY ABRASIVE PARTICLES, THE PARTICLES OF LOWER DENTISY, BEING ENCAPSULATED IN A METAL ENVELOPE, THE DENSITIES OF SAID ENCAPSULATED PARTICLES OF LOWER DENSITY BEING GREATER THAN THE DENSITY OF THE UNENCAPSULATED PARTICLES OF LOWER DENSITY, SAID ENCAPSULATED PARTICLES HAVIG A DENSITY MORE THAN 30 PERCENT OF THE DENSITY OF HIGHEST DENSITY, AND SAID PARTICLES BEING SUBSTANTIALLY UNIFORMLY DISTRIBUTED IN SAID METAL MATRIX.
Claim 3
Dependent Claim
29 words
The abrader of claim 1 in which said primary abrasive is diamond and said secondary abrasive is an inorganic compound having a hardness of at least about 1,250 kg/mm2.
Claim 4
Dependent Claim
23 words
The abrader of claim 1 in which the encapsulating metal is chosen from the group consisting of tungsten, tantalum, columbium, molybdenum and titanium.
Claim 5
Dependent Claim
29 words
In the abrader of claim 1 in which the secondary abrasive is metal encapsulated with a member of the group consisting of tungsten carbide and alumina and silicon carbide.
Claim 6
Dependent Claim
39 words
In the abrader of claim 4 in which the primary abrasive is metal encapsulated diamonds and the secondary abrasive is a member of the group consisting of metal encapsulated tungsten carbide, metal encapsulated alumina and metal encapsulated silicon carbide.
Claim 7
Dependent Claim
27 words
In the abrader of claim 1 in which the primary abrasive is diamond encapsulated with a metal and the secondary abrasive is alumina encapsulated with a metal.
Claim 8
Dependent Claim
22 words
The abrader of claim 1 in which the primary abrasive is diamond encapsulated with tungsten and the secondary abrasive is tungsten carbide.
Claim 9
Dependent Claim
24 words
The abrader of claim 1 in which the primary abrasive is diamond encapsulated with tungsten and the secondary abrasive is alumina encapsulated with tungsten.
Claim 10
Dependent Claim
25 words
The abrader of claim 1 in which the primary abrasive is diamond encapsulated with tungsten and the secondary abrasive is silicon carbide encapsulated with tungsten.
Claim 11
Dependent Claim
39 words
The abrader of claim 1 in which the primary abrasive is diamond encapsulated with tungsten and the secondary abrasive is tungsten carbide encapsulated with a metal having a specific gravity less than the specific gravity of the tungsten carbide.
Claim 12
Dependent Claim
23 words
The abrader of claim 10 in which the metal encapsulating the tungsten carbide is a metal having a specific gravity less than 15.
Claim 13
Dependent Claim
24 words
The abrader of claim 11 in which the metal encapsulating said tungsten carbide is cHosen from the group consisting of molybdenum, columbium, and titanium.
Claim 14
Dependent Claim
150 words
In a hot press process for producing a shaped abrasive in which an intimate mixture of primary and secondary abrasive particles and a powdered metal is positioned in a mold which is heated and subjected to elevated pressure on said mixture, the improvement in which said particles are composed of a primary abrasive having a hardness of above about 2,000 kg/mm2, and said secondary abrasive particle having a hardness in excess of about 1,250 kg/mm2, and less than the hardness of the primary abrasive particles, the primary abrasive particles having a different specific gravity from the specific gravity of the secondary abrasive particles, the primary or the secondary abrasive particles being encapsulated in a metal envelope, the densities of the encapsulated particles of lower density being more than 30 percent of the density of the particles of highest density and said particles being substantially uniformally distributed in said metal matrix.
Claim 15
Dependent Claim
150 words
In a hot press process for producing a shaped abrasive in which an intimate mixture of primary and secondary abrasive particles and a powdered metal is positioned in a mold which is heated and subjected to elevated pressure on said mixture, the improvement in which said particles are composed of a primary abrasive having a hardness of above about 2,000 kg/mm2, and said secondary abrasive particle having a hardness in excess of about 1,250 kg/mm2, and less than the hardness of the primary abrasive particles, the primary abrasive particles having a different specific gravity from the specific gravity of the secondary abrasive particles, the primary or the secondary abrasive particles being encapsulated in a metal envelope, the densities of the encapsulated particles of lower density being more than 30 percent of the density of the particles of highest density and said particles being substantially uniformally distributed in said metal matrix.
Claim 16
Dependent Claim
30 words
In the process of claim 13 in which said primary abrasive is diamond and said secondary abrasive is an inorganic compound having a hardness of at least about 2,000 kg/mm2.
Claim 17
Dependent Claim
26 words
In the process of claim 13 in which the encapsulating metal is chosen from the group consisting of tungsten, or tantalum, columbium (niobium) molybdenum and titanium.
Claim 18
Dependent Claim
30 words
In the process of claim 13 in which the secondary abrasive is chosen from the group consisting of metal encapsulated tungsten carbide metal encapsulated alumina and metal encapsulated silicon carbide.
Claim 19
Dependent Claim
38 words
In the process of claim 13 in which the primary abrasive is metal encapsulated diamonds and the secondary abrasive is chosen from the group consisting of metal encapsulated tungsten carbide, metal encapsulated alumina and metal encapsulated silicon carbide.
Claim 20
Dependent Claim
27 words
In the process of claim 13 in which the primary abrasive is diamond encapsulated with a metal and the secondary abrasive is alumina encapsulated with a metal.
Claim 21
Dependent Claim
23 words
In the process of claim 13 in which the primary abrasive is diamond encapsulated with tungsten and the secondary abrasive is tungsten carbide.
Claim 22
Dependent Claim
26 words
In the process of claim 13 in which the primary abrasive is diamond encapsulated with tungsten and the secondary abrasive is silicon carbide encapsulated with tungsten.
Claim 23
Dependent Claim
25 words
In the process of claim 13 in which the primary abrasive is diamond encapsulated with tungsten and the secondary abrasive is alumina encapsulated with tungsten.
Claim 24
Dependent Claim
40 words
In the process of claim 13 in which the primary abrasive is diamond encapsulated with tungsten and the secondary abrasive is tungsten carbide encapsulated with a metal having a specific gravity less than the specific gravity of the tungsten carbide.
Claim 25
Dependent Claim
24 words
In the process of claim 13 in which the metal encapsulating the tungsten carbide is a metal having a specific gravity less than 15.
Claim 26
Dependent Claim
22 words
In the process of claim 13 in which the encapsulating metal is chosen from the group consisting of molybdenum, columbium, and titanium.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-10-14 | 1978-04-15 | 1978-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-14 | 1982-04-15 | 1982-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-14 | 1986-04-15 | 1986-10-15 | $7700.00 | Window Closed / Lapsed |