It is difficult to say when abrasive technology had a beginning. Abrasives were used by man many thousands of years before he learned to write. Primitive man used abrasives for the sharpening of tools of wood, bone or flint. […] The beginning of the science of abrasives, however, may be taken as that time when man began to select certain rocks for their peculiar properties, and to fashion these into tools for grinding. [COES71],
Grits and bonding systems have been introduced in the previous two chapters and their impact on technological, environmental, economic and social sustainability has been discussed. Yet not only the ingredients, but also the design and type of tools define sustainable grinding process performance. Therefore, this chapter discusses abrasive tools distinguished by the cutting edge engagement (Fig. 1.1). In grinding with bonded or coated tools, the grit penetrates the workpiece bound to a path. Room-bound interaction takes place in lapping and polishing, where the grits roll between workpiece and a counterbody, often within slurry. In energy-bound abrasive processes, the grits are accelerated towards the workpiece material and dash particles out of the surface. The fourth active mechanism occurs when the tool is pressed with higher force but constant pressure onto the workpiece. Vibratory grinding and honing are considered to be mostly force-bound processes.
Grinding wheels are also known as bonded tools. The German Norm DIN 8589 specifies grinding processes by the machined workpiece area, wheel contact area, and feed direction [DIN03]. Most conventional grinding wheels consist of the conventional abrasives Al2O3 or SiC in a monolithic wheel body (Fig. 4.1 left). Superabrasive grits are more wear-resistant and expensive, so it is established that they are used in a thin abrasive layer on a wheel body. Depending on the bonding system, the abrasive layer is multi-layered and can be dressed (Fig. 4.1 middle) or mono-layered (Fig. 4.1 right).
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B. Linke, Life Cycle and Sustainability of Abrasive Tools,
RWTHedition, DOI 10.1007/978-3-319-28346-3_4
For high-speed machining, vitrified bonds have higher safety requirements on grinding tool toughness. High efficiency deep grinding requires tools with appropriate porosity and high toughness. Conventional grinding tools have gained competitiveness through low-temperature sintering bonds and enhanced abrasive grits. [KLOM86, p. 9]