High pressure and high temperature sintering of fine-grained PCD using bi-layered assembly

Abstract

This work presents the study of the synthesis and characterization of polycrystalline diamond (PCD) compacts using a bi-layered assembly method and solving the catastrophic nature of failure molding when using single-layered assembly and 0.5–1.5 μm diamond powder as starting materials. The well-sintered PCD compacts are prepared on WC-16wt% Co substrates at temperatures from 1350 °C to 1500 °C for 15 min at static high pressure of 5.2 GPa, using the bi-layered assembly method. According to our scanning electron microscope observation, the specimens sintered at 1450 °C have a homogeneous microstructure. The graphitization of the diamond appears at 1500 °C according to X-ray diffraction analysis. The specimens sintered at 1450 °C show the best performance according to the wear resistance test.

Keywords:

• polycrystalline diamond compacts
• high pressure and high temperature
• sintering
• diamond–diamond direct bonding

AMS Subject Classification :

• 74A40
• 74E15
• 74N15

Acknowledgements

This work is funded by Sichuan University and partially supported by the National Natural Science Foundation of China (Grant No. 50572067). The authors would like to thank HongJun Chen at Fact Abrasives ShangHai Co. for her assistance in preparing the diamond powder. The authors are very grateful to Dai Meng Di Ltd for preparing our samples and to Weiyuan Lu at YiJing Group for wear resistance tests.