Smith International, Inc.

Brian A White

Anthony Griffo

Zhigang Zak Fang

Kumar T Kembaiyan

Stewart N Middlemiss

Ron K Eyre

Madapusi K Keshavan

Thomas W Oldham

Robert M Denton

Alysia C White

Gary R Chunn

Saul N Izaguirre

Nathan R Anderson

Daniel J Belnap

A bit body formed of a mixture of matrix material and superabrasive powder and including pockets lined with superabrasive-free matrix material, and a method for forming the same, are provided. The pockets are shaped to receive cutting elements therein. The superabrasive-free matrix material enhances braze strength when a cutting element is brazed to surfaces of the pocket. The method for forming the drill bit body includes providing a mold and displacements. The displacements are coated with a mixture of superabrasive free matrix-material and an organic binder. The mold is packed with a mixture of matrix material and superabrasive powder and the arrangement heated to form a solid drill bit body. When the solid bit body is removed from the mold, pockets are formed by the displacements in the bit body and are lined with the layer of superabrasive-free matrix material. The superabrasive material may be diamond, polycrystalline cubic boron nitride, SiC or TiBin exemplary embodiments.

Bonding of cutters in diamond drill bits

A drill bit having a bit body having at least one blade thereon, at least one cutter pocket disposed on the at least one blade, at least one cutter disposed in the at least one cutter pocket, hardfacing applied to at least a selected portion of the drill bit is shown and described. The hardfacing includes a first hardfacing layer disposed on the selected portion of the drill bit, a second hardfacing layer disposed on the first hardfacing layer, wherein the first hardfacing layer has a hardness different than a hardness of the second hardfacing layer.

Layered hardfacing, durable hardfacing for drill bits

Polycrystalline diamond (PCD) carbide composites of this invention have a microstructure comprising a plurality of granules formed from PCD, polycrystalline cubic boron nitride, or mixture thereof, that are distributed within a substantially continuous second matrix region that substantially surrounds the granules and that is formed from a cermet material. In an example embodiment, the granules are polycrystalline diamond and the cermet material is cemented tungsten carbide. PCD carbide composites of this invention display improved properties of fracture toughness and chipping resistance, without substantially compromising wear resistance, when compared to conventional pure PCD materials.

Polycrystalline diamond carbide composites

Bonding of cutters in drill bits

PCD materials of this invention comprise diamond crystals that are bonded together with a catalyst/binder material. The PCD material is prepared by combining diamond grains with a catalyst/binder material either as a premixture or by infiltration during sintering. The PCD material comprises 15 percent by volume or less diamond grains sized 20 micrometers or less. The diamond grains are pressurized under elevated temperature conditions to form the desired PCD material. PCD materials of this invention can constitute the exclusive material phase of a PCD construction, or can form one or more material phase in a multi-phase material microstructure, wherein the multiple material phase can be arranged in an ordered/oriented or random fashion. PCD materials of this invention display improved properties of impact and fatigue resistance, and functional toughness, when used in complex wear environments, when compared to conventional PCs materials comprising intentionally added fine-sized diamond grains.

Polycrystalline diamond materials formed from coarse-sized diamond grains

Growing community of inventors

The Woodlands, TX, United States of America

Brian A White