摘要:
A compact blank for use in operations that require improved thermal stability, impact strength, and abrasion resistance is disclosed. The compact includes a substrate formed of tungsten carbide or other hard material with multiple abrasive diamond crystal layers bonded to the substrate. The abrasive diamond crystals are provided in successive layers of different size particles with the coarsest size particles being farthest away from the substrate. A catalyst is premixed with the diamond crystals in a weight percent which progressively decreases from the layer closest to the substrate through succeeding layers.
摘要:
A polycrystalline compact cutting element for use in operations that require high impact and abrasion resistance. The compact includes a substrate formed of tungsten carbide or other hard material with a diamond or cubic boron nitride layer bonded to a mounting surface on the substrate. The interface between the layers is defined by a three-dimensional topography formed with a plurality of surface irregularities in an arrangement whereby a straight line or a constant radii accurate line does not connect a series of adjacent surface irregularities.
摘要:
A high pressure/high temperature piston-cylinder-type apparatus has an electrically insulating diamond or cubic boron nitride coating disposed between one or both movable pistons and the surrounding core to electrically isolate the piston or pistons from the surrounding core. The electrically insulating coating is applied to the exterior surface of one or both of the pistons or, alternately, to the inner surface of the core. Electrically insulated, right circular cylindrical pistons are used at both ends of the apparatus resulting in the ability to uniformly compress reaction charges at high temperatures with a much higher length-to-diameter ratio. A ring of electrical insulating material is alternately mounted at the reaction charge end of each piston, with the remaining exterior surface of each piston coated with a thin, elastically insulating layer.
摘要:
A compact blank for use in operations that require very high abrasion resistance and a thermally stable cutting edge is disclosed. The compact comprises a substrate formed of tungsten carbide or other hard material with a polycrystalline diamond layer bonded to the substrate. The diamond layer is fabricated by chemical vapor deposition and then subsequently bonded to the tungsten carbide substrate by the application of high pressure and high temperature at diamond stable conditions.
摘要:
An apparatus and method of forming a composite body including the steps of forming a diamond material layer having a first surface from diamond crystals having a nitrogen content of less than 100 ppm; providing a substrate; and bonding the first surface of the diamond material layer and the substrate under high pressure and high temperature. The composite body has a diamond material layer formed from diamond crystals having a nitrogen content of less than 100 ppm. The diamond material layer has a first surface and a substrate. The first surface of the diamond material layer and the substrate are bonded together under high pressure and high temperature.
摘要:
A high pressure reaction vessel includes an inner bushing surrounding a reaction charge. The inner bushing is formed of at least one material having a low shear strength that undergoes a polymorphic phase change to a more dense phase within the operating pressure range of the reaction vessel. The bushing may be formed of at least two low shear strength materials with one of the materials undergoing polymorphic phase change to a more dense phase. The one of the two materials which undergoes a polymorphic phase change forms between 10% and 90% of the total volume of the inner bushing. In another embodiment, a pressure transmitting media and an electrical resistance heater tube are concentrically arranged within the inner bushing. The pressure transmitting media is formed of a low shear strength material that undergoes a polymorphic phase change to a more dense phase. In both embodiments, the low shear strength material undergoing polymorphic phase change is potassium bromide.
摘要:
A composite component suitable for high temperature applications which includes a composite compact that is thermally stable at temperatures up to 1200.degree. C., the composite compact including a thin layer of metal bonded directly to a polycrystalline table in a HP/HT press, and a metallic substrate joined to the thin layer of metal by a high strength braze joint. The method of fabrication includes the steps of: placing a high temperature braze filler metal on the upper surface of the substrate and in contact with the thin layer of metal; applying heat through the table to melt the filler metal and accomplish the high strength joint between the substrate and the thin layer of metal; and cooling the substrate by conducting heat from all but the upper surface thereof.
摘要:
Diamond or CBN polycrystalline abrasive grit useful in tools for grinding or cutting is made by size reducing and leaching non-diamond or non-CBN material from a compact greater than 1,000 microns in diameter to provide polycrystalline abrasive grit having a size of from about 1 to about 1,000 microns in diameter and having a network of inter-connected, empty pores dispersed throughout.
摘要:
A polycrystalline diamond cutting element for use in rock drilling or other operations that requires very high abrasion resistance with high transverse rupture strength at temperatures above 700 degrees centigrade. The cutting element includes a diamond layer that contains pre-sintered polycrystalline diamond agglomerate (PPDA) bonded to a supporting substrate. The PPDA can be made thermally stable and can be selected to produce a cutting element with any desired abrasion resistance characteristic without affecting internal stress.
摘要:
A polycrystalline diamond compact for use in cutting operations with a renewable sharp cutting edge, high abrasion resistance and high impact strength. The polycrystalline diamond is a composite composed of a matrix of coarse diamond interspersed with large agglomerated particles of ultra fine diamond. The agglomerated particles produce sharp cutting edges that are protected from impact forces by the overall uniform matrix of coarse diamond crystals. The self-sharpening cutter is highly resistant to spalling and catastrophic fracture.