Enhanced performance of PDC cutters with high-entropy alloy binders

ABSTRACT: Polycrystalline diamond compact (PDC) cutters are crucial cutting tools in oil drilling, geological exploration, and related industries, and their performance depends largely on the binder material. This study examines the impact of high-entropy alloy (HEA) binders on the microstructure, wear resistance, and thermal stability of PDC cutters. Eutectic HEA AlCoCrFeNi2.1 powder was mixed with diamond powder and sintered at high pressure (8.0 GPa) and high temperature (1600°C) to produce PDC cutters with different HEA contents. For comparison, conventional cobalt-bonded PDC cutters were also prepared. SEM images show that the HEA particles were not completely melted during the sintering process, but the molten HEA and cobalt infiltrated from the cemented carbide filled the gaps between the diamond particles. Wear resistance tests revealed that HEA-bonded PDC cutters exhibited significantly improved wear resistance compared to cobalt-bonded counterparts. Additionally, polycrystalline diamond (PCD) samples with HEA binders were fabricated using the infiltration method, and their thermal stability was evaluated. Thermal stability tests indicated that PCD samples with HEA binders demonstrated superior resistance to thermal degradation compared to those with cobalt binders. These findings offer valuable insights into optimizing PDC binder materials and lay the groundwork for the use of HEAs in the superhard materials industry.