円筒端面の正面フライス削りによる超硬材種の初期欠損性試験

抄録

It has been reported that the angle of engagement and disengagement have dominant influences on the tool life of a carbide face-milling cutter and may lead early to the fracture of carbide tips when they are over some critical values. In this study, the methods of facemilling of an end face of cylindrical workpiece or half and hollow-cylindrical workpieces prepared from rectangular blocks which allow continuous change of these angles simultaneously or either angle independently are proposed. Applying these methods, the properties of carbides on the early fracture before the occurrence of steady progression of wear are tested. The appearance of this tool failure is most unfavourable, showing the shortage of toughness of carbide tips for a given machining job.
As carbide tips of better wear resistance have generally less shock resistance, the test for early fracture due to the lack of toughness is considered to be necessary for the selection and estimation of suitable carbide tips. Test results show that the properties for early fracture of carbide tips of which toughness having been classified by the static toughness test can be evaluated dynamically and simply by the cutting methods mentioned above.