Cutting elements include a diamond-bonded body attached with a substrate. The substrate has a coercivity of greater than about 200 Oe, and has a magnetic saturation of from about 73 to 90. The diamond-bonded body has a compressive stress at the surface of greater than about 0.9 GPa after heat treatment, and greater than about 1.2 GPa prior to heat treatment.

Polycrystalline diamond may include a working surface and a peripheral surface extending around an outer periphery of the working surface. The polycrystalline diamond includes a first volume including an interstitial material and a second volume having a leached region that includes boron and titanium. A method of fabricating a polycrystalline diamond element may include positioning a first volume of diamond particles adjacent to a substrate, the first volume of diamond particles including a material that includes a group 13 element, and positioning a second volume of diamond particles adjacent to the first volume of diamond particles such that the first volume of diamond particles is disposed between the second volume of diamond particles and the substrate, the second volume of diamond particles having a lower concentration of material including the group 13 element than the first volume of diamond particles.

A cutting element has a thermally stable polycrystalline diamond layer formed on an upper side of a polycrystalline diamond layer. The cutting element has a cutting face opposite the polycrystalline diamond layer, a transition layer on a side of the polycrystalline diamond layer opposite the thermally stable polycrystalline diamond layer, and a non-planar interface between the transition layer and the polycrystalline diamond layer. The non-planar interface has a perimeter exposed around a side surface of the cutting element encircling an interior of the non-planar interface and an uppermost portion of the perimeter is a distance from the cutting face greater than an axial distance between the cutting face and the interior.

A milling tool includes a milling arm with a rotatable cutting element positioned on the milling arm. The rotatable cutting element may be fixed longitudinally and radially relative to a rotational axis of the rotatable cutting element in the milling arm while being rotatable about the rotational axis.

A variety of methods, systems, and apparatus are disclosed, including, in one embodiment, a drill bit, comprising: a bit body defining a rotational axis and having a plurality of cutter pockets formed thereon, each cutter pocket shaped to receive a respective substrate of a cutter; wherein each cutter pocket has an inner profile that defines an area of increased braze gap that conforms to an outer profile of the respective substrate; and a braze interface comprising a braze alloy disposed in each cutter pocket between the inner profile of the cutter pocket and the outer profile of the respective substrate, such that a thickness of the braze alloy is greater at the area of increased braze gap.

In an embodiment, a method of fabricating a polycrystalline diamond compact is disclosed. The method includes sintering a plurality of diamond particles in the presence of a metal-solvent catalyst to form a polycrystalline diamond body; leaching the polycrystalline diamond body to at least partially remove the metal-solvent catalyst therefrom, thereby forming an at least partially leached polycrystalline diamond body; and subjecting an assembly of the at least partially leached polycrystalline diamond body and a cemented carbide substrate to a high-pressure/high-temperature process at a pressure to infiltrate the at least partially leached polycrystalline diamond body with an infiltrant. The pressure of the high-pressure/high-temperature process is less than that employed in the act of sintering of the plurality of diamond particles.

Polycrystalline diamond constructions comprise a diamond body attached with a substrate during high pressure/high temperature processing, and include a modified reaction zone interposed between the body and substrate that is engineered to minimize or eliminate unwanted back diffusion of carbon from the diamond body into the substrate during the high pressure/high temperature processing.

A polycrystalline diamond (PCD) composite compact element has a body of polycrystalline diamond material and a cemented carbide substrate bonded to the body of polycrystalline material along an interface. The cemented carbide substrate has tungsten carbide particles bonded together by a binder material, the binder material including an alloy of Co, Ni and Cr. The tungsten carbide particles form at least 70 weight percent and at most 95 weight percent of the substrate and the binder material has between about 60 to 90 wt. % Ni, between about 10 to 40 wt. % Co, and about 0.25 to 1.0 wt % Cr.sub.3C.sub.2.

A cutter for a drill bit includes: a substrate for mounting the cutter to the drill bit; and a cutting table. The cutting table: is made from a superhard material, is mounted to the substrate, has an interface with the substrate at a lower end thereof, and has a working face at an upper end thereof. The working face has a protruding center section and a plurality of protruding ribs. Each rib extends radially outward from the center section to a side of the cutting table. Each rib has a triangular profile formed by a pair of inclined side surfaces and a ridge connecting opposing ends of the side surfaces. The working face further has a plurality of recessed bases located between adjacent ribs and each extending inward from the side.

A rotating cutter for a fixed cutter type bit includes an annular sleeve with a retainer having a plurality of inwardly extending tabs and a spindle cutter rotatably coupled to the annular sleeve. The spindle cutter includes a spindle extending into the annular sleeve and rotatable about a central axis of the annular sleeve, a base portion positioned between the retainer and a proximal end of the annular sleeve, and a cutter portion coupled to the spindle. The rotating cutter further includes at least one pin disposed between adjacent tabs of the plurality of tabs of the retainer to prevent axial movement of the base portion through the retainer.