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Materials Science

, Volume 35, Issue 6, pp 842–848 | Cite as

Longevity of tungsten-cobalt alloys under load in a corrosive environment

  • A. I. Bassarab
  • B. D. Vasyliv
  • A. D. Ivasyshyn
  • L. Ya. Chernyakhivs'kyi
  • I. Ya. Hotsanyuk
Science for Production
  • 22 Downloads

Abstract

We studied the influence of the chemical composition of the WC-Co cermet system on the operating characteristics of hard-alloy tips of drill bits manufactured from it. We established that the cyclic contact strength of tips in air at room temperature and the threshold range of the stress intensity factor in the tip material increase with the cobalt content. Using the results of tests of the materials for cyclic crack resistance, as well as of cavitation-erosion and electrochemical tests in 3% NaCl aqueous solutions, we ascertained that the optimum corrosion and mechanical characteristics correspond to the composition containing 8 mass% Co. We noticed a significant contribution of the anodic dissolution of the Co-phase and its hydrogen embrittlement in the process of corrosive-mechanical damage of hard alloys. We discovered a satisfactory correlation between the parameters of cyclic contact strength, threshold range of the stress intensity factor, and steady-state rate of cavitation-erosion failure of WC-Co hard alloys. This fact demonstrates the possibility to use these parameters as reliable and interchangeable criteria of the operational reliability of hard-alloy products.

Keywords

Stress Intensity Factor Hard Alloy Hydrogen Embrittlement Anodic Dissolution Crack Resistance 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Kluwer Academic/Plenum Publishers 2000

Authors and Affiliations

  • A. I. Bassarab
  • B. D. Vasyliv
  • A. D. Ivasyshyn
  • L. Ya. Chernyakhivs'kyi
  • I. Ya. Hotsanyuk

There are no affiliations available

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