非軸対称形状を有した刃先交換式ドリルの切削特性とMQLの適用効果

The cutting performance of indexable insert drill that has non-axisymmetrical geometry is investigated. A solid drill that has axisymmetrical and twisted geometry is also used to compare the cutting characteristics. The diameter of drills is 16mm and carbon steel is used as work material. The application effects of MQL that oil mist is supplied from oil holes in the tool are also examined. The temperature of peripheral corner edge of outer insert is measured using a two-color pyrometer with an optical fiber. The tool temperature of indexable insert drill is higher than that of solid drill and it reaches approximately 525°C at highest. On the other hand, the thrust force of indexable insert drill is lower than that of solid drill and it do not change so much with cutting speed. The surface roughness of indexable insert drill is approximately 1.15-5.4μm and this is higher than that of solid drill in each cutting speed. However, it is improved by supplying the oil mist