Tech Talk
Why use “Vitrified CBN Grinding Wheels”?
The increasing use of difficult-to-grind materials, tighter dimensional tolerances, improved quality, and tighter production schedules in all fields of manufacturing, have all contributed to bring about major advances in the grinding process over recent years.
Realistically, in cylindrical grinding the many different profiles and often limited production lot sizes impose certain restrictions on using vitrified CBN. Nevertheless, there are now many successful applications using vitrified CBN wheels that a CBN solution may be worth pursuing. IN the case of ID (internal cylindrical grinding) the use of vitrified CBN has become commonplace.
In contrast to metal bonded CBN wheels, vitrified CBN wheels can be produced with controlled porosity. The resulting chip chambers efficiently remove chips and thus heat from the workpiece and simultaneously enhance coolant delivery to the grinding zone. Loading of the wheel’s surface is thus prevented and, as a result, there is no generation of additional heat. Damage to the workpiece surface zone is therefore greatly reduced. Additionally, due to CBN’s superior thermoconductivity, the grinding process is generally cooler, thus reducing tensile stress while increasing compressive stress.
The open structure allows optimum penetration of the sharp-edged CBN grinding grains into the surface of the workpiece, resulting in excellent material removal capacity. The very significant wear resistance of the CBN grains yields considerable increases in production and cost savings.
