How PDC Cutting Tools Are Made

Polycrystalline Diamond Compact (PDC) cutting tools combine the extreme hardness of synthetic diamond with the impact resistance of a tungsten carbide substrate. They are widely used in oil and gas drilling, mining, and machining applications.

What is a PDC Cutter?

A PDC cutter consists of a thin layer of polycrystalline diamond (PCD) bonded to a tungsten carbide (WC-Co) substrate under high temperature and high pressure (HTHP) conditions. The diamond layer provides exceptional wear resistance and hardness, while the carbide substrate provides toughness and impact resistance.

Manufacturing Process

1. Diamond Powder Preparation

Synthetic diamond powder is selected based on grain size and purity. The diamond grains are typically in the range of 2–40 micrometers. The powder is cleaned and treated to remove impurities before being placed in the pressing assembly.

2. Substrate Preparation

The tungsten carbide substrate is manufactured through powder metallurgy processes. Tungsten carbide powder is mixed with cobalt binder, pressed into the desired shape, and sintered to form a dense, strong substrate.

3. High Pressure High Temperature (HPHT) Sintering

The diamond powder and carbide substrate are assembled in a press cell and subjected to extreme conditions:

• Pressure: 5–6 GPa (gigapascals)
• Temperature: 1,300–1,600°C
• Duration: 10–30 minutes

Under these conditions, the cobalt from the carbide substrate acts as a catalyst, promoting diamond-to-diamond bonding and creating a metallurgical bond between the PCD layer and the substrate.

4. Leaching (Optional)

For enhanced thermal stability, the cobalt catalyst can be leached from the diamond layer using acid treatment. This produces a thermally stable PDC (TSP) that can withstand higher temperatures without diamond degradation.

5. Finishing

After HPHT processing, the PDC cutters are ground, lapped, and polished to precise dimensions. The cutting edge may be chamfered or honed to improve performance in specific applications.

Applications

PDC cutters are used in:

• Drill bits — for oil and gas drilling, mining exploration
• Cutting tools — for machining non-ferrous metals, composites, and wood
• Wire drawing dies — for precision wire manufacturing
• Tunnel boring machines — for rock excavation

Advantages

• Exceptional wear resistance — 100x longer life than conventional carbide tools
• High impact toughness from the carbide substrate
• Excellent heat conductivity for efficient chip removal
• Can be manufactured in various shapes and sizes for different applications

SINO SEIKO（Sino Qtech Industries Co., Ltd.） provides a full range of PDC cutters and PCD/PCBN cutting tools for industrial applications worldwide. Contact us for custom solutions.