A Review of Attachment of Stratapax^R Using Gas Pressure Diffusion Bonding

The development of the gas pressure diffusion bonding technique for attachment of Stratapax^R diamond cutters to studs or bit blanks is reviewed in this paper. This paper updates the results presented previously on a continuing project conducted for the Division of Oil, Gas, Shale and In Situ Technology, Department of Energy. The process has been developed to a point where bonded parts can be obtained from commercial suppliers. A complete description is given of the latest bonding process including surface conditioning, metallization, canning, and gas pressure bonding. Results from experiments designed to facilitate reliable fabrication are included. Bond strengths of samples obtained from commercial suppliers have shear strengths (500 MPa) comparable to those developed at Sandia Laboratories. Results from laboratory drilling experiments are included. These tests were run to demonstrate the reliability of the bond in a cyclic load environment. With a suitable attachment technique and adequate cooling, the Stratapax has demonstrated superior cutting capabilities in rock with rates of penetration to 7.6 mm/s in Sierra White Granite.