In the realm of engineering rotary excavation, the rigid and brittle nature of the Polycrystal Diamond Compact (PDC) layer poses challenges to the impact resistance of conical teeth. This hinders their widespread adoption and utilization. In this paper, the Abaqus simulation is used. By optimizing the parameters of the radius of the cone top arc, we analyzed the changing law of the parameters of large-diameter D30 series conical PDC teeth, such as the equivalent force, impact force, and energy absorption of the conical teeth during the impact process, and optimized the best structure of the conical PDC teeth. After being subjected to a high temperature and high pressure, we synthesized the specimen for impact testing and analyzed the PDC layer crack extension and fracture failure. The findings reveal the emergence of a stress ring below the compacted area of the conical tooth. As the radius of the cone top arc increases, so does the area of the stress ring. When R ≥ 10 mm, the maximum stress change is minimal, and at R = 10 mm, the stress change in its top unit is relatively smooth. Optimal impact resistance is achieved, withstanding a total impact work value of 7500 J. Extrusion cracks appear in the combined layer part of PDC layers I and II, but the crack source is easy to produce in the combined layer of PDC layer II and the alloy matrix and extends to both sides, and the right side extends to the surface of the conical tooth in a "dragon-claw". The failure morphology of the conical teeth includes ring shedding at the top of the PDC layer, the lateral spalling of the PDC layer, and the overall cracking of the conical teeth. Through this study, we aim to promote the popularization and application of large-diameter conical PDC teeth in the field of engineering rotary excavation.
Keywords: conical PDC teeth; crack extension; impact resistance; large diameter; simulation.