Tech Talk
What is "CBN"?
In 1969, the General Electric Company introduced a new abrasive to the industry, cubic boron nitride - CBN as it is more commonly known. CBN is an abrasive with a hardness greater than that of silicon carbide and yet not as hard as diamond. CBN has the ability to machine even the hardest of steels to very precise forms and finishes with a great deal less wear than aluminum oxide or silicon carbide. Moreover, CBN is chemically inert in the presence of carbon. Unlike diamond, which is carbon based and has an affinity for the carbon in steels, CBN can machine steels at very high stock removal rates and with superior surface finishes. Compared with aluminum oxide and silicon carbide, CBN has minimal wear and therefore stays sharper for a longer period of time between truing and dressing. Because of its inherent sharpness CBN tends to machine cooler, providing high surface integrity and superior surface finish. The cost of the abrasive is high, however, the benefits derived from the virtual elimination of dressing and the quality of the workpiece surface may be advantageous.
