04729440 is referenced by 140 patents and cites 18 patents.

An earth boring apparatus is disclosed having bearing members comprised of transition layer polycrystalline diamond. The transition layer polycrystalline diamond bearings include a polycrystalline diamond layer interfaced with a composite transition layer comprising a mixture of diamond crystals and precemented carbide pieces subjected to high temperature/high pressure conditions so as to form polycrystalline diamond material bonded to the precemented carbide pieces. The polycrystalline diamond layer acts as the bearing surface. The transition layer bearings are preferably supported by a cemented tungsten carbide substrate interfaced with the transition layer.

Title
Transistion layer polycrystalline diamond bearing
Application Number
600399
Publication Number
4729440
Application Date
May 19, 1986
Publication Date
March 8, 1988
Inventor
David R Hall
Provo
UT, US
Agent
Willian Brinks Olds Hofer Gilson & Lione
Assignee
Smith International
CA, US
IPC
E21B 10/22
E21B 4/02
View Original Source