Norton Company

Frank J Csillag

Cristan Ellison-Hayashi

Morteza Zandi

Russell Lee Yeckley

Louis K Bigelow

Sy-Hwa Chen

James T Hoggins

Chien-Min Sung

Leo Merrill

Hyun S Cho

Shih-Yee Kuo

Dinesh K Shetty

Peter Kuo

Synthetic diamond film produced by chemical vapor deposition can be crushed to obtain diamond grit which has useful abrasive properties. The flexibility of CVD deposition processes in determining diamond film properties means that CVD diamond grit properties can be tailored to particular abrasive applications. In a disclosed embodiment, the grit particles are coated with a magnetic material. The coated grit particles can then be aligned with a magnetic field, and the coated grit particles are bonded to a matrix while aligned. In a further disclosed form of the invention, a chemical vapor deposition system, such as an arc jet plasma deposition system, is provided in a chamber.

Method for making diamond grit and abrasive media

A superhard form of boron suboxide comprises at least about 95% by weight B.sub.6 O and has a KNH.sub.100 value of at least about 3800 kg/mm.sup.2. In a preferred embodiment, the boron suboxide has an average grain size of about 0.1-40 microns. A method for forming the superhard boron suboxide comprises mixing boron oxide (B.sub.2 O.sub.3) and boron powder and subjecting the mixture to a temperature of 1500.degree. C. to about 2,200.degree. C. and a pressure sufficient to produce the superhard boron suboxide. The superhard boron suboxide may be made by this method with or without a sintering aid being present in the mixture of boron and boron oxide.

Boron suboxide material and method for its preparation

A superhard form of boron suboxide (B.sub.x O) comprises at least about 95% by weight of polycrystalline B.sub.6 O and has a KHN.sub.100 value of at least about 3800 kg/mm.sup.2. A method for forming the superhard boron suboxide comprises mixing stoichiometric amounts of boron oxide (B.sub.2 O.sub.3) powder and boron powder and subjecting the mixture to a temperature of about 1800.degree. C. to about 2200.degree. C. and a pressure of about 2,000 to about 6,000 psi while encapsulated by boron nitride. The boron powder comprises about 90 to 95% by weight of elemental boron (B), and at least about 1% by weight of a sintering aid, such as Mg.

Superabrasive cutting elements, backed compacts and methods for their manufacture are disclosed wherein metal coated superabrasive particles are cemented under HPHT conditions. The superabrasives bond to the metal of the coating and the metal coatings of adjacent particles bond to each other forming a matrix. A binding aid with thermal expansion characteristics close to that of the superabrasive particle can be infiltrated through or otherwise mixed with the particles to assist in the bonding between the metal coatings and to fill in voids. Catalyst and non-catalyst binding aids can also be used. Uncoated, smaller superabrasive particles can be interstitially dispersed among the coated particles to increase the superabrasive concentration and can self bond to form a cemented/sintered structure. Tungsten is a preferred metal coating and silicon is a preferred binding/sintering aid. The superabrasive can be diamond, cubic boron nitride, boron doped diamond or crushed sintered polycrystalline aggregates. The free-standing cutting element can have a brazeable layer and the compact can be backed with, for example, cemented tungsten carbide. Free-standing cutting elements can be thermally stable up to 1,200.degree. C. Backed compacts can be thermally stable up to 1,100.degree. C.

Cemented and cemented/sintered superabrasive polycrystalline bodies and

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Westboro, MA, United States of America

Frank J Csillag