Abstract:
The present invention relates to polycrystalline ultra hard material cutting elements, and more particularly to a method of forming a polycrystalline ultra hard material cutting element with a thicker ultra hard layer than cutting elements formed by prior art methods. In an exemplary embodiment, such a method includes pre-sintering the ultra hard material powder to form an ultra hard material layer that is partially or fully densified prior to HPHT sintering, so that the ultra hard layer is pre-shrunk. This pre-sintering in an exemplary embodiment is achieved by means of a spark plasma process, or in another exemplary embodiment by a microwave sintering process.
Abstract:
A solid-state far ultraviolet light emitting element is formed by a hexagonal boron nitride single crystal, excited by electron beam irradiation to emit far ultraviolet light having a maximum light emission peak in a far ultraviolet region at a wavelength of 235 nm or shorter.
Abstract:
Superabrasive tools and methods for the making thereof are disclosed and described. In one aspect, superabrasive particles are chemically bonded to a matrix support material according to a predetermined pattern by a braze alloy. The brazing alloy may be provided as a powder, thin sheet, or sheet of amorphous alloy. A template having a plurality of apertures arranged in a predetermined pattern may be used to place the superabrasive particles on a given substrate or matrix support material.
Abstract:
A composite material consists of a plurality of cores dispersed in a matrix. The cores are formed of ultra-hard material, or the components for making an ultra-hard material. The matrix is formed of the components for making an ultra-hard material of a grade different to that of the cores, and a suitable binder. The ultra-hard material is polycrystalline in nature and is typically PCD or PcBN. The cores are typically provided as granules coated with the components for making an ultra-hard material and the binder. The composite material typically takes on a honeycomb structure of an ultra-hard material and cores within the pores of the honeycomb structure bonded to the honeycomb structure. The pores of the honeycomb structure may be ordered or random.
Abstract:
The present invention relates to polycrystalline ultra hard material cutting elements, and more particularly to a method of forming a polycrystalline ultra hard material cutting element with a thicker ultra hard layer than cutting elements formed by prior art methods. In an exemplary embodiment, such a method includes pre-sintering the ultra hard material powder to form an ultra hard material layer that is partially or fully densified prior to HPHT sintering, so that the ultra hard layer is pre-shrunk. This pre-sintering in an exemplary embodiment is achieved by means of a spark plasma process, or in another exemplary embodiment by a microwave sintering process.
Abstract:
An improved assembly for HPHT processing having a can with an opening and a mixture disposed within the opening. A sealant barrier is positioned atop the mixture. First and second lids are positioned atop the mixture. A meltable sealant positioned intermediate the second lid and a cap covering the opening.
Abstract:
An improved method for synthesizing superabrasive particles provides high quality industrial superabrasive particles with high yield and a narrow size distribution. The synthesis method can include forming a growth precursor of a substantially homogeneous mixture of raw material and catalyst material or layers of raw material and metal catalyst. The growth precursor can have a layer of adhesive over at least a portion thereof. A plurality of crystalline seeds can be placed in a predetermined pattern on the layer of adhesive. The growth precursor can be maintained at a temperature and pressure at which the superabrasive crystal is thermodynamically stable for a time sufficient for a desired degree of growth. Advantageously, the patterned placement of crystalline seeds and disclosed processes allow for production of various morphologies of synthetic diamonds, including octahedral and cubic diamonds, and improved growth conditions generally. As a result, the grown superabrasive particles typically have a high yield of high quality particles and a narrow distribution of particle sizes.
Abstract:
An improved method for controlling nucleation sites during superabrasive particle synthesis can provide high quality industrial superabrasive particles with high yield and a narrow size distribution. The synthesis method can include forming a raw material layer, forming a particulate catalyst layer adjacent the raw material layer, and placing crystalline seeds in a predetermined pattern at least partially in the catalyst layer or raw material layer to form a growth precursor. Alternatively, the raw material and catalyst material can be mixed to form a particulate crystal growth layer and then placing the crystalline seeds in a predetermined pattern in the growth layer. Preferably, seeds can be substantially surrounded by catalyst material. The growth precursor can be maintained at a temperature and pressure at which the superabrasive crystal is thermodynamically stable for a time sufficient for a desired degree of growth. The crystalline seeds can be placed in a predetermined pattern using a template, a transfer sheet, vacuum chuck or similar techniques. The superabrasive particles grown using the described methods typically have a high yield of high quality industrial particles and a narrow distribution of particle sizes.
Abstract:
A method for removing defects at high pressure and high temperature (HP/HT) or for relieving strain in a non-diamond crystal commences by providing a crystal, which contains defects, and a pressure medium. The crystal and the pressure medium are disposed in a high pressure cell and placed in a high pressure apparatus, for processing under reaction conditions of sufficiently high pressure and high temperature for a time adequate for one or more of removing defects or relieving strain in the single crystal.
Abstract:
Methods of synthesizing polycrystalline bodies using rhombohedral graphite materials are disclosed and described. One procedure includes providing a particulate graphite source having a majority of carbon atoms oriented in a rhombohedral polytype configuration. The particulate graphite source can be shaped into a desired shape having a porosity from about 0% to about 30%. A sufficient amount of heat and pressure can be applied to the desired shape to form diamond and consolidate the diamond into a polycrystalline body.