What is industrial diamond?

Industrial diamond, any diamond that is designated for industrial use, principally as a cutting tool or abrasive.
Industrial diamonds are too badly flawed, irregularly shaped, poorly coloured, or small to be of value as gems, but they are of vital importance in the modern metalworking and mining industries.
Their utility stems from the fact that diamond is the hardest natural substance known.



- rough diamonds not qualified as gem but still perfect for tools.





Types of diamonds used in tooling

When you looking for diamond tools you may find abbreviations such as ND,MCD,PCD ... Let's see what are they and what is the difference.

The main difference is the source, diamond used in tools can be natural  ( ND ) or synthetic.

Most natural diamonds have ages between 1 billion and 3.5 billion years. Most were formed at depths between 150 and 250 kilometres in the Earth mantle under high pressure and temperature. Tens to hundreds of million years ago, they were carried to the surface in volcanic eruptions.  

Since the early XX. century scientists had try to develop a method to create synthetic diamond. The first reproducible synthesis was reported around 1955.
They can be grown from high-purity carbon under high pressures and temperatures (HPHT) or from hydrocarbon gas by chemical vapor deposition (CVD).
 



ND:
     Natural Diamond, when a diamond not qualified as a gem (color flaw, small in size) can be used for industrial purpose. Using for jewellery designs it gives high gloss finish and long service life.


- natural diamond for industrial use

MCD:   Mono-Crystal Diamond made artificially in many shapes for different diamond tooling applications. Most commonly used for diamond tools. Yellowish color. High gloss finish and long service life just as natural diamonds.


- Mono-Crystal Diamonds

PCD:    Poly-Crystal Diamond made by sintering many micro-size single diamond crystals at high temperature and high pressure, so it has less glossy finish, hardness is similar to tungsten carbide tools but 10-20x life time.




PDC:    Polycrystalline Diamond Composite (or Compacts) are made by combining some layers of polycrystalline diamonds (PCD) with a layer of cemented carbide liner at high temperature and high pressure. PDC has the advantages of diamond’s high wear resistance with carbide’s good toughness.


- Layered PDC 

Plated diamond tools:  These tools are made by fixing the diamonds onto the tool's base via electroplating method or via CVD (Chemical Vapor Deposition) method.


They can usually be made to good processing precision. 

 


What is tungsten carbide?

Although it is not diamond we have to mention tungsten carbide as its widely used in CNC milling tools production.

Tungsten carbide (chemical formula: WC) is a chemical compound containing equal parts of tungsten and carbon atoms.


In its most basic form, tungsten carbide is a fine gray powder, but it can be pressed and formed into shapes. 

Carbides are usually cost less than PCD tool but have shorter lifetime as well.



 

 




Examples in jewelry applications

 

ND and MCD gives a smooth and extremely shiny finish and fairly popular in jewelry industry. You can find them on numerous types of machine and hand tools.

PCD, PDC, and carbide tools has a more rough surface  (in microscopic level) and have different role. They applied in CNC end mills or drill bits and some special tools used for create rainbow effect and other dull backgrounds.






It was a brief guide about the most common diamond applications in tooling. Hope you like it and if you have any question, just leave a comment below