被削材除去過程における切りくずの観察

Abstract

Metal removal mechanism by abrasive grit haven't investigated so much. But it is very important problem in grinding mechanism. In order to clear the action of abrasive grit which produce chips, we must get authentic informations about it. Then, a quick-stop technique has been developed to freeze the chip forming process effectively in nominal grinding speed. And the optical micrograph of longitudinal cross-section in the center of the groove has been got and observed in details. This paper concerns with an investigation into the chips produced in front of the rake surface of edge. The relations between the shape of chip and cutting condition have been discussed and as results followings were clarified:(1) The chips formed by the edges having apex angle of 100°-140° are consist of short segment with shear deformation. But the free ends of chips change depending on the apex angle of edges.(2) The chips are strongly compressed during the removing process between the material and the front surface of edge, and the free ends of chips shall get round in the case of large apex angle.(3) The number of cracks in the free end of chip shall increase when the oil is put on the work surface, and the change of chip-type is observed for small apex angle of cutting edge.(4) The increase of cutting speed makes the term of removing material as a chip short and makes the size of chip small accordingly.