A single-crystal diamond includes a pair of main surfaces facing each other, an impurity concentration being changed along a first direction in each of the main surfaces.

A diamond die includes a diamond provided with a hole for drawing a wire material, the diamond being a CVD single-crystal diamond, an axis of the hole being inclined relative to a normal direction of a crystal plane of the diamond.

Embodiments of the invention relate to polycrystalline diamond (PCD) exhibiting enhanced diamond-to-diamond bonding. In an embodiment, PCD includes a plurality of diamond grains defining a plurality of interstitial regions. A metal-solvent catalyst occupies at least a portion of the plurality of interstitial regions. The plurality of diamond grains and the metal-solvent catalyst collectively exhibit a coercivity of about 115 Oersteds (Oe) or more and a specific magnetic saturation of about 15 Gauss.Math.cm.sup.3/grams (G.Math.cm.sup.3/g) or less. Other embodiments are directed to polycrystalline diamond compacts (PDCs) employing such PCD, methods of forming PCD and PDCs, and various applications for such PCD and PDCs in rotary drill bits, bearing apparatuses, and wire-drawing dies.

A composite sintered body includes a first phase and a second phase. The first phase is a diamond phase, and the second phase is a phase formed of one or more types of elements or compounds or both thereof and applying strain to the first phase. A contained amount of the second phase is larger than 0 ppm and not larger than 1000 ppm. As a result, there is provided a high wear-resistant, high local wear-resistant, and high chipping-resistant diamond-containing composite sintered body.

Embodiments of the invention relate to polycrystalline diamond (PCD) exhibiting enhanced diamond-to-diamond bonding. In an embodiment, PCD includes a plurality of diamond grains defining a plurality of interstitial regions. A metal-solvent catalyst occupies at least a portion of the plurality of interstitial regions. The plurality of diamond grains and the metal-solvent catalyst collectively exhibit a coercivity of about 115 Oersteds (Oe) or more and a specific magnetic saturation of about 15 Gauss.Math.cm.sup.3/grams (G.Math.cm.sup.3/g) or less. Other embodiments are directed to polycrystalline diamond compacts (PDCs) employing such PCD, methods of forming PCD and PDCs, and various applications for such PCD and PDCs in rotary drill bits, bearing apparatuses, and wire-drawing dies.

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.

A composite sintered body includes a diamond phase and a non-diamond carbon phase. A non-diamond carbon phase occupancy rate is higher than 0% and not higher than 30%. The non-diamond carbon phase occupancy rate is a percentage of an area of the non-diamond carbon phase to a total area of one arbitrarily specified cross section of the composite sintered body. As a result, there is provided a high wear-resistant, high local wear-resistant and high chipping-resistant diamond-containing composite sintered body suitably used as a material for a wear-resistant tool, a cutting tool and the like.

A composite sintered body includes a first phase and a second phase. The first phase is a diamond phase, and the second phase is a phase formed of one or more types of elements or compounds or both thereof and applying strain to the first phase. A contained amount of the second phase is larger than 0 ppm and not larger than 1000 ppm. As a result, there is provided a high wear-resistant, high local wear-resistant, and high chipping-resistant diamond-containing composite sintered body.

Embodiments of the invention relate to polycrystalline diamond (PCD) exhibiting enhanced diamond-to-diamond bonding. In an embodiment, PCD includes a plurality of diamond grains defining a plurality of interstitial regions. A metal-solvent catalyst occupies at least a portion of the plurality of interstitial regions. The plurality of diamond grains and the metal-solvent catalyst collectively exhibit a coercivity of about 115 Oersteds (Oe) or more and a specific magnetic saturation of about 15 Gauss.Math.cm.sup.3/grams (G.Math.cm.sup.3/g) or less. Other embodiments are directed to polycrystalline diamond compacts (PDCs) employing such PCD, methods of forming PCD and PDCs, and various applications for such PCD and PDCs in rotary drill bits, bearing apparatuses, and wire-drawing dies.

Embodiments of the invention relate to polycrystalline diamond (PCD) exhibiting enhanced diamond-to-diamond bonding. In an embodiment, PCD includes a plurality of diamond grains defining a plurality of interstitial regions. A metal-solvent catalyst occupies at least a portion of the plurality of interstitial regions. The plurality of diamond grains and the metal-solvent catalyst collectively exhibit a coercivity of about 115 Oersteds (Oe) or more and a specific magnetic saturation of about 15 Gauss.Math.cm.sup.3/grams (G.Math.cm.sup.3/g) or less. Other embodiments are directed to polycrystalline diamond compacts (PDCs) employing such PCD, methods of forming PCD and PDCs, and various applications for such PCD and PDCs in rotary drill bits, bearing apparatuses, and wire-drawing dies.