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.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
