The vitrified bond for conventional abrasive tools is the oldest matrix used for bonded abrasives. Since the early 1960's Meister has developed all of the bonds which it uses for complete process control in-house.
The introduction of the vitrified sintered corundum tools counts as a major technological advance. Even on older-generation machines, these tools provide huge reductions in process costs.
The key to the success of this bond system which has become so essential to high-productivity serial processes, is in the outstanding abrasive properties of these largely porous structures, its outstanding receptiveness to contouring and dressing, and the high stock-removal volumes which its good wear properties can achieve.
The structure of a vitrified abrasive wheel can be classically characterised in a ternary system by the following elements:
- the abrasive (or its chemical and physical properties)
- the bond
- the resulting microstructure
The available grades of corundum, silicon carbide and sintered corundum crystals offer a wide range of cutting properties and are selected for specific applications.
Most vitrified bonds are made from frits, feldspar, kaolin and different clays.
Their chemical and physical properties are determined ultimately by the combination of raw materials, the grit sizes that are used and the firing cycle, i.e. vitrification.
The microstructure is a function of the relative proportions of abrasive grits and their specific mix of type and size, bond content and residual pore volume, and is an essential precondition for an efficient tool.
The toolmaker's know-how consists of his judicious choice of individual components and the very closely controlled production process.