ＣＦＲＰ（炭素繊維強化プラスチック）の切削機構に関する研究 Ｉ 極低速切削速度下における加工面生成機構

Abstract

Cutting mechanism of CFRP(Carbon Fiber Reinforced Plastics) have been studied. Unidirectional prepreg were adopted to investigate effects of fiber orientation (fiber angles) and tool rake angles on the chip formation. Direct SEM observation of cutting experiments revealed that CFRP cutting had three types of chip formation: delamination, fiber buckling and fiber cutting type, which were determined by the fiber angles and the tool rake angles. Delamination and fiber buckling type appeared on fiber angle 0 deg. cutting. The other cutting conditions offered fiber cutting type, which had continuous and discontinuous chip formation. Fiber cutting type provided the machined surface with different appearance from the others. A number of the fiber ends appeared on the machined surface. The rugged fiber ends allowed irregularities on the machined surface. Most of the fibers on the machined surface had a few cracks in close vicinity to the ends. Cutting forces were significantly affected by the fiber angles. The fiber angle effects on the tangential force were greater than those on normal force. Fiber angle 15-45° cuttings offered the minimum cutting force on every rake angle in fiber cutting type. In case of chip elimination space angle γ< 30°, difficulties in chip elimination produced extensive irregular morphology surface.