A cutting insert includes a tool carrier having a body with a pocket, and a cutting tip affixed to the pocket by brazing. The pocket is defined by a vertical back wall and a horizontal support surface. A notch is formed at the intersection between the vertical back wall and the horizontal support surface. The notch has a non-planar first portion proximate the vertical back wall and formed with a radius, R1, and a planar second portion extending between the first portion and the horizontal support surface and formed at an inclination angle with respect to a plane parallel to the horizontal support surface of the pocket. The design of the notch significantly reduces thermal stress and eliminates the formation of cracks in the pocket of the tool carrier when using an injection molding process to form the tool carrier.

A cutting insert includes a tool carrier having a body with a pocket, and a cutting tip affixed to the pocket by brazing. The pocket is defined by a vertical back wall and a horizontal support surface. A notch is formed at the intersection between the vertical back wall and the horizontal support surface. The notch has a non-planar first portion proximate the vertical back wall and formed with a radius, R1, and a planar second portion extending between the first portion and the horizontal support surface and formed at an inclination angle with respect to a plane parallel to the horizontal support surface of the pocket. The design of the notch significantly reduces thermal stress and eliminates the formation of cracks in the pocket of the tool carrier when using an injection molding process to form the tool carrier.

A cutting insert includes a tool carrier having a body with a pocket, and a cutting tip affixed to the pocket by brazing. The pocket is defined by a vertical back wall and a horizontal support surface. A notch is formed at the intersection between the vertical back wall and the horizontal support surface. The notch has a non-planar first portion proximate the vertical back wall and formed with a radius, R1, and a planar second portion extending between the first portion and the horizontal support surface and formed at an inclination angle with respect to a plane parallel to the horizontal support surface of the pocket. The design of the notch significantly reduces thermal stress and eliminates the formation of cracks in the pocket of the tool carrier when using an injection molding process to form the tool carrier.

A polycrystalline diamond sintered material tool includes: a cemented carbide substrate, which is mainly composed of WC and includes Co; and a diamond layer containing a metal catalyst made of Co provided on the cemented carbide substrate. The average layer thickness of a Co rich layer formed in an interface between the cemented carbide substrate and the diamond layer is 30 m or less. C.sub.MAX/C.sub.DIA is 2 or less when C.sub.DIA is an average content of Co included in the diamond layer and C.sub.MAX is a peak value of a C.sub.O content in the Co rich layer. D/D.sub.O is less than 2 when D is an average grain size of WC particles in a region from the interface between the cemented carbide substrate and the diamond layer to 50 m toward an inside of the cemented carbide substrate; and D.sub.O is an average grain size of WC particles.

A method for manufacturing a cubic boron nitride cutting tool including a base metal and sintered cubic boron nitride compact at a corner portion of the base metal, capable of improving the accuracy of the center height and reducing the angle of inclination or width of a negative rake face; and the cubic boron nitride cutting tool. The method includes grinding the compact by pressing it against an end face of a grindstone of a grinder to form flank and rake faces on the compact while the base metal of the cutting tool is held by a chuck of the grinder, so that the compact is substantially ground. The rake face is formed to be recessed from a top face of the base metal or only a portion of the compact that protrudes from a base-metal rake face is ground while the tool is continuously held by the chuck.

A method for manufacturing a cubic boron nitride cutting tool including a base metal and sintered cubic boron nitride compact at a corner portion of the base metal, capable of improving the accuracy of the center height and reducing the angle of inclination or width of a negative rake face; and the cubic boron nitride cutting tool. The method includes grinding the compact by pressing it against an end face of a grindstone of a grinder to form flank and rake faces on the compact while the base metal of the cutting tool is held by a chuck of the grinder, so that the compact is substantially ground. The rake face is formed to be recessed from a top face of the base metal or only a portion of the compact that protrudes from a base-metal rake face is ground while the tool is continuously held by the chuck.

A composite member in which WC-based cemented carbide members are bonded to each other via a bonding layer formed by solid phase diffusion bonding of a bonding member made of a Ti foil. The bonding layer is constituted by first layers adjacent to the WC-based cemented carbide members and made of a TiC phase and a metal W phase in which an average area ratio of the TiC phase is 40 to 60%. The bonding layer also includes second layers adjacent to the first layers and made of a TiCo phase and a metal Ti phase in which an average area ratio of the TiCo phase is 50 to 95%, and a residual Ti layer.

A composite member in which WC-based cemented carbide members are bonded to each other via a bonding layer formed by solid phase diffusion bonding of a bonding member made of a Ti foil. The bonding layer is constituted by first layers adjacent to the WC-based cemented carbide members and made of a TiC phase and a metal W phase in which an average area ratio of the TiC phase is 40 to 60%. The bonding layer also includes second layers adjacent to the first layers and made of a TiCo phase and a metal Ti phase in which an average area ratio of the TiCo phase is 50 to 95%, and a residual Ti layer.

Cutting elements include a substrate, a thermally stable polycrystalline table comprising a superhard material secured to the substrate, and a layer of metal interposed between, and attaching the substrate and the thermally stable polycrystalline table. Methods of forming a cutting element include providing a thermally stable polycrystalline table in a mold, providing a layer of metal on the thermally stable polycrystalline table, distributing a mixture of particles comprising a plurality of hard particles and a plurality of particles comprising a matrix material on the layer of metal, and heating the mold while applying pressure to the mixture of particles to cause the mixture of particles to coalesce and form a substrate and at least partially melt the layer of metal to flow and wet the thermally stable polycrystalline table and the substrate to form an attachment therebetween.

A cutting tool includes a cutting edge member. The cutting edge member forms a corner portion. The cutting edge member includes a cutting edge formed at the intersection of a rake surface and a flank, at least two breaker wall surfaces and at least one convex portion. The cutting edge includes a first cutting edge and a second cutting edge connected thereto. The second cutting edge is situated at the corner portion. Each breaker wall surface is formed to extend along the cutting edge. The convex portion is formed between the two breaker wall surfaces spaced from each other to protrude relatively toward the cutting edge side. A part of the convex portion is situated around a connecting portion of the first and second cutting edges.