Especially for vitrified bonded grinding wheels, the chip space can often also be enlarged by so-called free grinding. The basic prerequisite for this is the self — sharpenability of the grinding wheel.
In the free grinding process, the grinding wheel topography is adjusted to the demands of the subsequent grinding process by means of a gradual increase of the material removal rate. By means of this kind of multistage free grinding, the maximum achievable material removal rate Qw can be significantly increased without the danger of grinding wheel clogging.
Removal Sharpening
For metallically bonded grinding wheels, sharpening process that follow the principle of spark-erosion (EDM) and electrolysis (ECM) can be applied. Spark — erosion is based on discharge processes between the two electrodes grinding wheel and sharpening tool while using a non-conductive dielectric. Electrochemical removal includes the decomposition of the anodally polarised grinding wheel bond in a suitable electrolyte. The methodological principles are described in detail in “Manufacturing Processes Volume 3”.
Even with large grit diameters, it is possible to create a sufficient grain protrusion beyond the bond level via chemical sharpening principles.