Polycrystalline Wire Dies

Definition

Polycrystalline is made from chemically grown single crystals bonded together with a metal catalyst, under ultra high compression and thermal parameters. It has significant advantages over natural diamonds due to its high resistance to breakage and wear. In applications that do not require ultra high surface finishes on wire, this material is ideal.

Grain Structure

The polycrystalline has several grain structures for wire drawing applications. One, three, five, 10, 12, 25 & 50 microns Average Particle Size (APS) is presently available. The smaller APS produces a higher polish on the wire surface whereas the larger APS provides longer die life. The 10 & 12 micron APS can provide the best of both requirements. Either offers a good wire finish yet still contains superb wear resistance. The polycrystalline comes in three structures:

  • Carbide Supported - Containing a carbide ring around the PCD to help support the PCD. Carbide supported is available in all diamond sizes.
  • Self-Supported - PCD is non-supported and usually mounted with a low thermal soldier or adhesion compound. It is available in mid to small diamond sizes.
  • Thermally Stable – The metal catalyst which is contained in the bonding material is acid leached, resulting in the polycrystalline accepting higher temperatures. This material is ideal when drawing molybdenum or tungsten.

History

As a founding member of the ADDMA – “American Diamond Die Manufacturers Association” assisted in the development of the “D” designation. This designation separates the different size PCD available.