What is CBN and how does it compare to diamond as an abrasive?
This is an interesting question in the sense that you cannot reach a concrete answer. In other words you cannot say that one is better than the other.
How ever we have done some experiments that show that CBN outperforms diamond in certain applications.
Cubic Boron Nitride is a synthetic abrasive that is not soluble in alloys like nickel and iron. It can withstand higher temperatures than diamond although it is not as hard. Since diamond is soluble in ferrous alloys CBN is great at something diamond is not.
For the experiment we have used Kovar material which is a nickel-cobalt ferrous alloy.
When diced with diamond the burrs on this material are enormous and the cuts look very ugly.
The CBN blade seems to dice through this material with much more ease. The cuts look much better and the burr diminished significantly. We measured an average of 21 micron burr with CBN compared to 150 micron with diamond.
The pictures taken with our high power microscope illustrate this perfectly.
In conclusion CBN might not be better than diamond at everything but it is certainly much more effective with ferrous alloys. CBN has the same success for these type of materials than diamond has for materials like glass, quartz, sapphire, and ceramics.
Further test will follow to determine the best CBN grit size for materials like Copper, Nickel, Titanium, Silver, and Aluminium.