Strength of functionally designed cellular cemented carbides produced by coextrusion
In an effort to improve the wear characteristics of petroleum drill bit inserts, a series of cemented carbide materials with a functionally designed cellular (FDC) architecture were fabricated by a coextrusion process. The FDC architecture characterized in this study was comprised of cemented carbide cells surrounded by a ductile cobalt cell boundary. Property evaluation employed transverse rupture strength (TRS) testing to characterize their mechanical behavior. It was determined that the presence of Co2 + x W4 − x C in the material greatly affected the bonding of the cell to the cell boundary and therefore the strength of the material. Fractography of the FDC materials supported the hypothesis that the interface between the cell and cell boundary was affected by the Co2 + x W4 − x C phase and the consequential reduction in cobalt content of the cell.
KeywordsCobalt Wear Resistance Cell Boundary Cell Material Cobalt Content
The authors would like to thank Brian White and Greg Lockwood of Smith Bits, and Jeff Rodelas of University of Missouri-Rolla for their hard work and input on testing, processing, and other characterization. We would like to thank Kennametal Engineered Products (Traverse City, MI) for performing the ROC processing. For his help in producing the cemented carbides powders in this study, and coordinating the ROC processing we would like to thank Jonathan Bitler of Kennametal AMSG (Rogers, AR).
- 1.Brookes KJA (1996) World Directory and Handbook of Hardmetals and Hard Materials, 6 th ed., International Carbide Data, East Barnet, Hertfordshire, UK, p 26Google Scholar
- 3.Fang Z, Lockwood G, Griffo A (1999) Metall Mater Tran A 30A(12):3231Google Scholar
- 4.Landwehr S, Hilmas G, Huang T, Griffo A, White B (2003) Adv Powd Metall Partic Mat 6–163Google Scholar
- 5.Coblenz WS (1988) U.S. Patent No. 4,772,524Google Scholar
- 11.Hilmas G, Brady A, Abdali U, Zywicki G, Halloran J (1995) Mat Sci Eng A195:263Google Scholar
- 12.Popovic’ D, Halloran J, Hilmas GE, Brady GA, Somers S, Barda A, Zywicki G (1997) U.S. Patent No. 5,645,781Google Scholar
- 14.Timm EE (1988) Proc Adv Hard Mat Prod, 9–1Google Scholar
- 15.Lizenby JR, Lizenby KJ, Barnard LJ (1987) U.S. Patent 4,656,002Google Scholar