Four major processes connect the abrasive layer with the tool body: adhesive sealing, sintering, shrinking, and electroplating [KRAF08]. With electroplating, the
Table 5.3 Mechanisms in connecting abrasive layer and body [MARI04, p. 212]
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abrasive layer is directly deposited on the metallic body or on a metal ring. Abrasive layers of other bond types are either shrunk or sintered directly on the body or glued with adhesives.
For resin bonded tools, shrinking takes place during the resin hardening process. The inner surface of the mold is coated with a release agent to prevent adhesion of the resin and to ensure safe demolding. Oil based liquids might be used as release agents and can easily be sprayed onto the mold surface. The interface between the resin bond and the body is equipped with a first primer coat to ensure excellent bonding.
Glues connecting the abrasive rim layer and the body are often two component epoxy glues, but the exact composition of the glue is confidential information. Any thermal dilatation will disable the grinding tool [METZ86, p. 63]. Table 5.3 shows the basic mechanisms that connect the abrasive layer to wheel bodies of different materials. After combining abrasive layer and wheel body, the abrasive layer is post-processed by profiling, sharpening, and balancing for wheels of a diameter larger than 150 mm [METZ86, p. 63]. The centrifugal forces lead to radial and tangential stresses in the connection zone [HELL05b]. The Young’s modulus can be changed at a constant density through different bonding systems (resin or vitrified bond) [HELL05b].