Abstract: A cutting element having a cutting table made from sheet segments of commingled ultra hard material and binder. Each segment may be made from a finer or a coarser grade of ultra hard material or from different types of ultra hard material. The segments are aligned side by side over a cutting face of the cutting element to form the cutting table. The material grade and/or the material type of each segment may alternate across the cutting face.

Abstract: The present invention provides a cutting element having a cylindrical body having a canted end face on which is formed a ultra hard material layer. One or a plurality of transition layers may be provided between the ultra hard material layer and the cutting element body.

Abstract: Enhanced inserts are formed having a cylindrical grip and a protrusion extending from the grip. An ultra hard material layer is bonded on top of the protrusion. The inserts are mounted on a rock bit and contact the earth formations off center. The ultra hard material layer is thickest at a critical zone which encompasses a major portion of the region of contact between the insert and the earth formation. Transition layers may also be formed between the ultra hard material layer and the protrusion so as to reduce the residual stresses formed on the interface between the ultra hard material and the protrusion.

Abstract: A non-uniform interface is formed between a polycrystalline ultra hard material layer and a cemented tungsten carbide substrate, or a polycrystalline ultra hard material layer and a transition layer, or a transition layer and a substrate of a cutting element. A first sheet made from an intermediate material is formed and embossed on one face forming a non-uniform pattern raised in relief on the face. The embossed sheet is placed on a face of a presintered substrate. An ultra hard material sheet is formed and embossed, forming a non-uniform face complementary to the non-uniform face on the sheet of intermediate material. The ultra hard material sheet is placed over the intermediate material sheet so that the complementary faces are adjacent to each other. The assembly of substrate and sheets is sintered in a HPHT process.

Abstract: This invention is directed to cutting elements having an ultra hard cutting layer such as polycrystalline diamond or polycrystalline cubic boron nitride bonded on a cemented carbide substrate. The interface between the substrate and the cutting layer of each such cutting element is non-planar. The non-planar interface is designed to enhance the operating life of the cutting element by reducing chipping, spalling, partial fracturing, cracking and/or exfoliation of the ultra hard cutting layer, and by reducing the risk of delamination of the cutting layer from the substrate.

Abstract: A cutting element having a body which includes a grip portion from which extends a protrusion which is concentric to the grip portion. The diameter of the grip portion is larger than the diameter of the protrusion. Moreover, the upper portion of the protrusion has a larger diameter than the base of the protrusion. An ultra hard material cutting layer is formed on top of the protrusion and grip, covering and surrounding the protrusion resulting in a cutting layer that is mechanically interlocked with the body of the cutting element. A transition layer may be incorporated between the protrusion and the ultra hard material layer. The transition layer is preferably encapsulated by the ultra hard material layer.

Abstract: A method for manufacturing cutting tools having diamond-like cutting edges or surfaces which are formed by bonding high shear compaction diamond or cubic boron nitride (CBN) ropes or strips in helical grooves formed on the cutting tool outer surface. The strips are formed by slitting a sheet of high shear compaction diamond or CBN material. The ropes are formed by rolling the strips between grooved rollers.

Abstract: A polycrystalline diamond layer is bonded to a cemented metal carbide substrate by this process. A layer of dense high shear compaction material including diamond or cubic boron nitride particles is placed adjacent to a metal carbide substrate. The particles of diamond have become rounded instead of angular due to high shear compaction in a multiple roller process. The volatiles in the high shear compaction material are removed and binder decomposed at high temperature, for example, 950.degree. C., leaving residual amorphous carbon or graphite in a layer of ultra hard material particles on the carbide substrate. The substrate and layer assembly is then subjected to a high pressure, high temperature process, thereby sintering the ultra hard particles to each other to form a polycrystalline ultra hard layer bonded to the metal carbide substrate.