중절삭 밀링가공에서 부등각 엔드밀의 절삭특성 분석

An Analysis Cutting Characteristics in Heavy Cutting Milling Process with Different Angle Endmills

The chatter vibration, occuring in the machining process by endmill, has bad effects on the life of tool, productivity and accuracy of machining surface, due to the relative vibration between the workpiece and the tool. A conventional endmill which all four blades are 30° helix angles and a different helix angle endmill which the opposite two blades are 30° and the other opposites are different helix angles were studied. In this study, in order to find the endmill which is directly available in industry and has an excellent anti-vibration effect with less machining error. Machining error was increased in case of 3mm cutting depth, due to the deflection of the endmill and the deformation of specimen, as helix angle increases. In the surface roughness, as RPM was increased, the surface quality was improving. We obtained that a type(30°+33°) showed the most excellent surface in case of 3mm cutting depth in down milling, and in case of up milling a type(30°+30°) showed the most excellent surface.