Nowadays many kinds of coating materials are applied to tungsten carbide drill bits, which improve much the tool life and function of tungsten carbide drill bits, and here below are some of the most common ones:

 

1.Black oxide: it is an inexpensive black coating. A black oxide coating provides heat resistance and lubricity, as well as corrosion resistance. It increases the life of bits.

 

2.Titanium nitride (TiN): it is a very hard ceramic material that can be used to coat a tungsten carbide drill bit (usually a twist bit), extending the cutting life by three or more times. However, when the bit is sharpened the new edge will not have the benefits of the coating.

 

3.Titanium aluminum nitride (TiAlN): it is a similar coating that can extend tungsten carbide drill bit life five or more times.

 

4.Titanium carbon nitride (TiCN) is another coating also superior to TiN.

 

5.Diamond powder is used as an abrasive, most often for cutting tile, stone, and other very hard materials. Large amounts of heat are generated by friction, and diamond coated drill bits often have to be water cooled to prevent damage to the bit or the workpiece.

 

6.Zirconium nitride has been used as a tungsten carbide drill bit coating for some tools under some famous brand name.

 

 

(The End)