CHEMICAL REACTIONS OF THE GRINDING INTERFACE

The chip-forming process during grinding is characterized by extremely small depths of cut and high speed. Under these conditions the metal is observed to oxidize very rapidly in air to produce the well known spark shower. Of more importance, however, is the reduction in grinding interface. The grinding of mild steel, stainless steel and titanium in inert atmospheres has been found to be almost impossible due to the high cutting forces encountered. To date, it has not been possible to unequivocally identify the mechanisms by which chemical reactants aid grinding. Among the hypotheses thus far advanced, the following appear to agree most closely with the observed phenomenon: (1) the reaction products prevent adhesion of the abrasive grain to the metal; (2) the chemical reaction prevents workhardening of the metal; and (3) the reaction products prevent rewelding of the chips and the workpiece.