1. Raw Material and Equipment Preparation
Equipment: A domestic CS–XIII type hinge-style cubic press is used for synthesis.
Materials: Specially proportioned diamond micropowder and cemented carbide (as the substrate) are selected.
2. High-Temperature High-Pressure (HPHT) Sintering This is the critical step for forming the polycrystalline diamond composite structure.
Process Conditions: The assembled raw materials are placed in the press and sintered at temperatures of 1300–1600°C and pressures of 5.5–7.5 GPa. This process creates the initial composite blank, combining the diamond powder with the carbide to achieve high hardness and toughness.
3. Subsequent Shaping and Processing The sintered blank must undergo precision machining to form the final non-planar structure.
Procedures: These include sandblasting, cylindrical grinding, and lapping.
Forming: Through these steps, the blank is shaped into specific non-planar geometries, such as ridge (dual-edge), 3-ridge, 4-ridge, and 5-ridge structures.
4. Cutting Edge Angle Design and Control Controlling the geometric angle of the cutting edge is a crucial process parameter for optimizing performance.
Basic Design: Initially, the angle between the cutting edge and the vertical direction is set to 90°.
Optimization: To further enhance fatigue impact resistance, the process involves adjusting this angle to be greater than 90° (e.g., 99°). Experiments prove that this modification significantly boosts impact resistance while maintaining wear resistance and load performance.