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Publication numberUS3879901 A
Publication typeGrant
Publication dateApr 29, 1975
Filing dateSep 10, 1973
Priority dateJun 24, 1970
Publication numberUS 3879901 A, US 3879901A, US-A-3879901, US3879901 A, US3879901A
InventorsCaveney Robert John
Original AssigneeDe Beers Ind Diamond
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Metal-coated diamonds in a metal alloy matrix
US 3879901 A
Abstract
A compact comprising substantially graphite-free diamond particles having a continuous coating of titanium or molybdenum held in a matrix into which the titanium or molybdenum can diffuse. The matrix may for example, be an alloy selected from the group of Fe/Ni, Ni/Co/Cr/Fe, Fe/Si and Ti/Si alloys. The invention also provides a method of making such a compact by mixing the desired metal powders in suitable proportions with the coated diamond particles and compacting the mixture under pressure and temperature conditions in the diamond stable zone.
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Description  (OCR text may contain errors)

United States Patent [191 Caveney Apr. 29, 1975 1 METAL-COATED DIAMONDS IN A METAL ALLOY MATRIX [75] Inventor: Robert John Caveney,

Johannesburg, South Africa [73] Assignee: De Beers Industrial Diamond Division Limited, Johannesburg, South Africa 22 Filed: Sept. 10, 1973 211 Appl. No.: 395,457

Related US Application Data [63] Continuation of Scr. No. 153,105, June 14, 1971,

abandoned.

[30] Foreign Application Priority Data June 24, 1970 South Africa 70/4347 [52] US. Cl 51/295; 5 l/309 [51] Int. Cl B24d 3/06 [58] Field of Search 51/295, 309

[56] References Cited UNITED STATES PATENTS 3.239.321 3/1966 Blaine) ct a1. 51/309 3,306,720 2/1967 Darrow 51/309 3,316,073 4/1967 Kelso 51/295 3,351,543 11/1967 Vanderslice 51/309 3,356,473 12/1967 Hull et a1. 51/309 3,464,804 9/1969 Kuratomi.... 51/309 3/1972 Farkas 51/309 Primary E.\'aminerDonald J. Arnold Attorney, Agent, or FirmYoung & Thompson [57] ABSTRACT 5 Claims, No Drawings METAL-COATED DIAMONDS IN A METAL ALLOY MATRIX This is a continuation of application Ser. No. 153,105, filed June 14, 1971, and now abandoned.

This invention relates to compacts and it is an object of the present invention to provide a compact having improved properties over compacts of the prior art.

According to the invention there is provided a compact comprising substantially graphite-free diamond particles having a continuous coating of titanium or molybdenum held in a matrix compatible with the titanium or molybdenum coating. The term compatible means that the matrix must be such as allow diffusion of the titanium or molybdenum into it.

The matrix may be an alloy selected from the group of Fe/Ni, Ni/Co/Cr/Fe, Fe/Si, Ti/Si, Ti/Ni and Ti/Fe a1- loys, but is preferably one of the following alloys: Nil- Co/Cr/Fe:: 34/18/14/5 Fe/Ni:: 12/5 Fe/Si:: 63/2 All the above-mentioned ratios are weight for weight.

The matrix may also advantageously be tungsten carbide bonded with a transition metal of the 8th group, preferably cobalt. The transition metal is preferably present in the amount of about 10 percent by weight of the tungsten carbide.

The thickness of the titanium or molybdenum coat would normally be of the order of 1,000 to 2,000A, but coats of greater thickness can also be used.

The titanium or molybdenum coated diamonds for use in the compacts may be prepared by methods known to the art. The coating may, for example, be deposited on to the diamond surface by the method of vacuum deposition described in Vacuum Deposition of Thin Films" by L. Holland, Chapman and Hall, 1st Edition 1956. In order to create a titanium/diamond or molybdenum/diamond bond, as the case may be, the coated diamond may be heated to a temperature of greater then 500C to form the desired bond. However, this heating is not necessary as the during compact manufacture temperatures above 500C are encountered and the bond formation can therefore be obtained during the compact manufacture.

Further according to the invention, there is provided a method of making a compact including the steps mixing diamond particles having a continuous coating of titanium or molybdenum with a matrix material suitable to provide, on compaction, a matrix compatible with the titanium or molybdenum coating of the particles and compacting the mixture under pressure and temperature conditions in the diamond stable zone.

The diamond stable zone is a set of conditions known to the art and the Applicant refers to Berman R, and Simon F, Z. Elektrochem, Vol 59, 1955 page 333 in this regard.

Preferably, the pressure during compaction is about 60 kilobars and the temperature is between about 1,200 and 1,400C.

Embodiments of the invention will now be described.

Diamond compacts having a variety of matrices were prepared in the following manner:

ln all cases, diamond grit having a continuous titanium or molybdenum coating and the metal powders necessary to make the desired alloy were weighed into a plastic bottle. If for example, an iron/nickel alloy 12:5) was desired then 12 parts by weight of iron powder and 5 parts by weight of nickel powder were weighed into the bottle. The metal powders and grit were then mixed by placing the bottle in a milling machine for about 20 minutes. The mixture was placed in a graphite mould and loaded into a standard synthesis capsule. 1f the synthesis volume was not completely filled by the mould, compacted graphite was added to the capsule to fill the balance of the volume.

The mixture was then subjected to compaction for about five minutes at a pressure of about 60 kilobars and a temperature of between l,200 and 1,400C. These temperatures and pressures are in the diamond stable zone.

Using the above-mentioned method a number of diamond compacts were manufactured. Table I below sets out the diamond grit particle size and the matrix material used in these compacts.

In all the above cases, the diamond content of the compacts was 65% Vol/Vol.

The above mentioned compacts were compared in properties with a compact comprising uncoated diamond grit in a titanium-silicon matrix and it was found on an average that the grinding efficiency ratios of the invented compacts were greater than 1. The efficiency ratio is the ratio of wear under a set of abrading conditions of the invented compact to the wear under the same set of conditions of the standard compact times a conversion factor. The conversion factor reflects the differing densities of the matrices.

A value of greater than 1 indicates that the invented compact has superior abrasion resistance to the standard compact. Of the results, the most significant were those obtained for the compacts having Fe/Ni, WC bonded with 10% Co, Ni/Co/Cr/Fe, and Fe/Si matrices where the efficiency ratios were found to be 1.59, 4.53, 3.79 and 1.50, respectively.

We claim:

1. A compact consisting essentially of substantially graphite-free diamond particles having a continuous metal coating of thickness from 1,000 to 2,000A chemically bonded thereto and held in a matrix by a diffu sion alloy of the metal and the matrix at the metal/matrix interface, the metal being selected from the group consisting of titanium and molybdenum and the matrix being selected from the group consisting of Fe/Ni, Nil- Co/Cr/Fe and Fe/Si alloys and WC bonded with a transition metal of the V111 group, said compact having a grinding efficiency ratio greater than 1.

2. A compact according to claim 1, wherein the matrix is an Fe/Ni alloy the ratio of iron to nickel in the alloy being 12/5.

3. A compact according to claim 1, wherein the matrix is a Ni/Co/Cr/Fe alloy, the ratio of the metals in the alloy being 34/18/14/5. I

4. A compact according to claim 1 wherein the matrix is an Fe/Si alloy the ratio of the iron to the silicon in the alloy being 63/2.

5. A compact according to claim I wherein the matrix is WC bonded with cobalt which is present in the amount of about 10 percent by weight of the WC.

Patent Citations
Cited PatentFiling datePublication dateApplicantTitle
US3239321 *Nov 29, 1963Mar 8, 1966Adamant Res LabDiamond abrasive particles in a metal matrix
US3306720 *May 28, 1964Feb 28, 1967Gen ElectricMethod for the production of diamond compact abrasives
US3316073 *Aug 2, 1961Apr 25, 1967Norton CoProcess for making metal bonded diamond tools employing spherical pellets of metallic powder-coated diamond grits
US3351543 *May 28, 1964Nov 7, 1967Gen ElectricProcess of coating diamond with an adherent metal coating using cathode sputtering
US3356473 *May 28, 1964Dec 5, 1967Gen ElectricMetal-bonded diamond abrasive body
US3464804 *Apr 11, 1967Sep 2, 1969Takeo KagitaniMethod of chemically bonding carbon-titanium alloy to a diamond surface
US3650714 *Mar 4, 1969Mar 21, 1972Permattach Diamond Tool CorpA method of coating diamond particles with metal
Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3929432 *Sep 18, 1973Dec 30, 1975De Beers Ind DiamondDiamond particle having a composite coating of titanium and a metal layer
US3986303 *May 15, 1975Oct 19, 1976Norton CompanyRadially adjustable grinding wheel for grinding concave surfaces to constant primary and secondary radii
US4063909 *Sep 9, 1975Dec 20, 1977Robert Dennis MitchellAbrasive compact brazed to a backing
US4084942 *Aug 27, 1975Apr 18, 1978Villalobos Humberto FernandezUltrasharp diamond edges and points and method of making
US4108614 *Mar 31, 1977Aug 22, 1978Robert Dennis MitchellAbrasive body
US4142869 *Mar 22, 1977Mar 6, 1979Vereschagin Leonid FCompact-grained diamond material
US4184853 *Apr 21, 1976Jan 22, 1980Andropov Jury IIndividual abrasive grains with a silicon-base alloy coating
US4211294 *Apr 21, 1978Jul 8, 1980Acker Drill Company, Inc.Nickel, manganese alloy
US4373934 *Aug 5, 1981Feb 15, 1983General Electric CompanyMetal bonded diamond aggregate abrasive
US4452325 *Sep 27, 1982Jun 5, 1984Conoco Inc.Composite structure for cutting tools
US4534934 *Oct 20, 1981Aug 13, 1985General Electric CompanyAxial sweep-through process for preparing diamond wire die compacts
US4738689 *Oct 16, 1986Apr 19, 1988General Electric CompanyPolycrystalline self-boned diamond particles with metal coating
US4943488 *Nov 18, 1988Jul 24, 1990Norton CompanyLow pressure bonding of PCD bodies and method for drill bits and the like
US4951427 *May 30, 1989Aug 28, 1990General Electric CompanyRefractory metal oxide coated abrasives and grinding wheels made therefrom
US5011514 *Jul 11, 1989Apr 30, 1991Norton CompanyHard particles with metal coating as matrix; high strength cutting tools
US5024680 *Nov 7, 1988Jun 18, 1991Norton CompanyDiamond, chromium carbide and metal carbide multilayer
US5030276 *Nov 18, 1988Jul 9, 1991Norton CompanyCoating with a metal which is a carbide former on portion contacting metal matrix carrier
US5096465 *Dec 13, 1989Mar 17, 1992Norton CompanySuperhard metal-coated particles, binder alloy, drill bits for soft rock formations such as shale
US5104422 *Jul 13, 1990Apr 14, 1992General Electric CompanyRefractory metal oxide coated abrasives and grinding wheels made therefrom
US5116568 *May 31, 1991May 26, 1992Norton CompanyMethod for low pressure bonding of PCD bodies
US5151107 *Jul 29, 1988Sep 29, 1992Norton CompanyAbrasive cutters of multilayer structure
US5224969 *Apr 13, 1992Jul 6, 1993Norton CompanyDiamond having multiple coatings and methods for their manufacture
US5308367 *Aug 20, 1992May 3, 1994Julien D LynnTitanium-nitride and titanium-carbide coated grinding tools and method therefor
US5588975 *May 25, 1995Dec 31, 1996Si Diamond Technology, Inc.Coated grinding tool
US5681653 *May 11, 1995Oct 28, 1997Si Diamond Technology, Inc.Diamond cutting tools
US5731079 *Jan 31, 1996Mar 24, 1998Si Diamond Technology, Inc.Diamond cutting tools
US6319608May 15, 2000Nov 20, 2001General Electric CompanyTitanium chromium alloy coated diamond crystals for use in saw blade segments and method for their production
US6447569 *Jul 12, 2000Sep 10, 2002Kimiko SuetaCutting material where the diamond particles serve as cutting agents while being fixed in a retaining matrix which is titanium or a titanium and nickel alloy; knives, scissors, razors
US6641918May 30, 2000Nov 4, 2003Powdermet, Inc.Method of producing fine coated tungsten carbide particles
US7806206Feb 15, 2008Oct 5, 2010Us Synthetic CorporationSuperabrasive materials, methods of fabricating same, and applications using same
US8151911Aug 17, 2010Apr 10, 2012Us Synthetic CorporationPolycrystalline diamond compact, methods of fabricating same, and rotary drill bit using same
US8316969Jun 16, 2006Nov 27, 2012Us Synthetic CorporationSuperabrasive materials and methods of manufacture
US8448727Mar 7, 2012May 28, 2013Us Synthetic CorporationRotary drill bit employing polycrystalline diamond cutting elements
US8602132Oct 24, 2012Dec 10, 2013Us Synthetic CorporationSuperabrasive materials and methods of manufacture
DE2827425A1 *Jun 22, 1978Jan 11, 1979De Beers Ind DiamondVerfahren zum verbinden eines diamantcompacts oder kubischem bornitrid
DE3714353A1 *Apr 29, 1987Nov 17, 1988Inst Sverkhtverdykh MatProcess for producing a diamond-containing composite material
EP0012631A1 *Dec 18, 1979Jun 25, 1980De Beers Industrial Diamond Division (Proprietary) LimitedCoated abrasive pellets and method of making same
EP0352811A1 *Jul 28, 1989Jan 31, 1990Norton CompanyThermally stable superabrasive products and methods of manufacture thereof
EP0503974A1 *Mar 13, 1992Sep 16, 1992General Electric CompanyMultigrain abrasive particles
WO1987007197A1 *May 22, 1986Dec 3, 1987Carl F ClineMethod for production of cermets of abrasive materials
Classifications
U.S. Classification51/295, 51/309
International ClassificationC22C26/00, C09K3/14, B01J3/06
Cooperative ClassificationB01J3/062, C09K3/1445, B01J2203/066, B01J2203/0685, C22C26/00, B01J2203/0655, B01J2203/062
European ClassificationB01J3/06B, C09K3/14C2, C22C26/00