Abstract:
A method for treating a super-hard structure, the method including heating the super- hard structure to a treatment temperature of at least 500 degrees centigrade and cooling the super-hard structure from the treatment temperature to a temperature of less than 200 degrees centigrade at a mean cooling rate of at least 1 degree centigrade per second and at most 100 degrees centigrade per second to provide a treated super-hard structure. A PCBN structure produced by the method may have flexural strength of at least 650 MPa.
Abstract:
Polycrystalline compacts include hard polycrystalline materials comprising in situ nucleated smaller grains of hard material interspersed and inter-bonded with larger grains of hard material. The average size of the larger grains may be at least about 250 times greater than the average size of the in situ nucleated smaller grains. Methods of forming polycrystalline compacts include nucleating and catalyzing the formation of smaller grains of hard material in the present of larger grains of hard material, and catalyzing the formation of inter-granular bonds between the grains of hard material. For example, nucleation particles may be mixed with larger diamond grains, a carbon source, and a catalyst. The mixture may be subjected to high temperature and high pressure to form smaller diamond grains using the nucleation particles, the carbon source, and the catalyst, and to catalyze formation of diamond-to-diamond bonds between the smaller and larger diamond grains.
Abstract:
An abrasive compact may include an ultra-hard phase that may include ultra-hard particles having a Knoop hardness of 5000 KHN or greater, a sinter catalyst, and a reaction phase that may include a catalyst-ceramic compound having a Knoop hardness lower than that of the ultra-hard phase.
Abstract:
An insert for a cutting tool and a method of making an insert are provided. The insert for a cutting tool may comprise a body and a substrate carrier. The body may have a top, a bottom, and a plurality of side walls connected to the top and the bottom. The body may comprise superhard particles in absence of a support. The substrate carrier may have a recess. The bottom and the sidewall of the body may be adapted to be affixed to the recess of the substrate carrier.
Abstract:
A superhard structure comprises a body of polycrystalline superhard material comprising a first region and a second region, the second region being adjacent an exposed surface of the superhard structure, the second region comprising a diamond material or cubic boron nitride, the density of the second region being greater than 3.4x103 kilograms per cubic metre when the second region comprises diamond material. The material(s) forming the first and second regions have a difference in coefficient of thermal expansion, the first and second regions being arranged such that this difference induces compression in the second region adjacent the exposed surface. The first/a further region has the highest coefficient of thermal expansion of the polycrystalline body and is separated from a peripheral free surface of the body of polycrystalline superhard material by the second region or one or more further regions formed of a material or materials of a lower coefficient of thermal expansion. The regions comprise a plurality of grains of polycrystalline superhard material. There is also disclosed a method of making such a material.
Abstract:
Polycrystalline compacts include hard polycrystalline materials comprising in situ nucleated smaller grains of hard material interspersed and inter-bonded with larger grains of hard material. The average size of the larger grains may be at least about 250 times greater than the average size of the in situ nucleated smaller grains. Methods of forming polycrystalline compacts include nucleating and catalyzing the formation of smaller grains of hard material in the present of larger grains of hard material, and catalyzing the formation of inter-granular bonds between the grains of hard material. For example, nucleation particles may be mixed with larger diamond grains, a carbon source, and a catalyst. The mixture may be subjected to high temperature and high pressure to form smaller diamond grains using the nucleation particles, the carbon source, and the catalyst, and to catalyze formation of diamond-to-diamond bonds between the smaller and larger diamond grains.
Abstract:
A particular method includes uniaxially hot pressing a preform that includes abrasive particles in a bonding material to form a bonded abrasive body.
Abstract:
Diamond bonded constructions include a diamond body comprising intercrystalline bonded diamond and interstitial regions. The body has a working surface and an interface surface, and may be joined to a metallic substrate. The body has a gradient diamond volume content greater about 1.5 percent, wherein the diamond content at the interface surface is less than 94 percent, and increases moving toward the working surface. The body may include a region that is substantially free of a catalyst material otherwise disposed within the body and present in a gradient amount. An additional material may be included within the body and be present in a changing amount. The body may be formed by high-pressure HPHT processing, e.g., from 6,200 MPa to 10,000 MPa, to produce a sintered body having a characteristic diamond volume fraction v. average grain size relationship distinguishable from that of diamond bonded constructions form by conventional-pressure HPHT processing.
Abstract:
Der Erfindung liegt die Aufgabe zugrunde, Werkstoffe, welche Kohlenstoffnanoteilchen enthalten, für Bauteile zu verwenden, von denen neue komplexe Kombinationen von Eigenschaften sowie von statischer und dynamischer Belastbarkeit unterschiedlichen Charakters gefordert werden. Diese Aufgabe wird für die Gruppe der genannten Werkstoffe durch Verwendungen gelöst, für welche mindestens zwei der nachfolgend aufgeführten Eigenschaften oder Anforderungen maßgeblich sind: - Bearbeitbarkeit von Funktionsflächen in hoher Oberflächenqualität, - chemische Resistenz insbesondere bei hohen Einsatztemperaturen, - Korrosionsbeständigkeit insbesondere bei hohen Einsatztemperaturen, - Verschleißfestigkeit insbesondere bei hohen Einsatztemperaturen, - Verschleissfestigkeit unter elektrischer und/oder Strahlenbelastung, - geringer Reibungskoeffizient insbesondere bei hohen Einsatztemperaturen, - gute Wärmeleitfähigkeit sowie - einstellbare stoffliche Zusammensetzung zur Erzielung bestimmter physikalischer Eigenschaften. Diese Erfindung ist beispielsweise für Presswerkzeuge, Umformeinrichtungen, Lagerteile, Gusseinrichtungen, heat sinks und dergleichen insbesondere bei hohen Temperaturen anwendbar, ohne darauf beschränkt zu sein.