摘要
Polycrystalline diamond compacts (PDC) were synthesized using diamond powder of average crystal size 3-20 μm by the Ni 70 Mn 25 Co 5 alloy infiltration technique at high temperature and high pressure (HPHT).The surface residual stress of polycrystalline diamond (PCD) layer was measured using micro-Raman spectroscopy with hydrostatic stress model and X-ray diffraction (XRD).Measurements of the stress levels of PCDs show that the residual compressive stresses range from 0.12 to 0.22 GPa,which increase with the crystal size of diamond.Scanning electron microscopy (SEM) was used to observe the morphology of initial diamond grains and PCD cross-section.The results indicate that PCD has a dense and interlaced microstructure with diamond-diamond (D-D) direct bonding.And the smaller the crystal size of diamond,the better the growth of diamond direct bonding and the smaller the binder metal between diamond boundaries will be.
Polycrystalline diamond compacts （PDC） were synthesized using diamond powder of average crystal size 3-20 μm by the Ni 70 Mn 25 Co 5 alloy infiltration technique at high temperature and high pressure （HPHT）.The surface residual stress of polycrystalline diamond （PCD） layer was measured using micro-Raman spectroscopy with hydrostatic stress model and X-ray diffraction （XRD）.Measurements of the stress levels of PCDs show that the residual compressive stresses range from 0.12 to 0.22 GPa,which increase with the crystal size of diamond.Scanning electron microscopy （SEM） was used to observe the morphology of initial diamond grains and PCD cross-section.The results indicate that PCD has a dense and interlaced microstructure with diamond-diamond （D-D） direct bonding.And the smaller the crystal size of diamond,the better the growth of diamond direct bonding and the smaller the binder metal between diamond boundaries will be.
基金
supported by the National Natural Science Foundation of China (Grant Nos.50572032,50801030 and 50731006)
