| 摘要 |
A throwaway insert (10) enables reduction in cutting force and improves chip separation ability without sacrificing the strength of cutting edge (17) thereof. An upper face (12) of the throwaway insert (10) is provided with an undulating portion (16), which is formed by alternately arranged concave portions (14) and convex portions (15), so as to provide a wavy shape to the cutting edge (17). The undulating portion (16) comprises four concave portions (14), i.e., a first deep-concave portion (14A), a first shallow-concave portion (14B), a second deep-concave portion (14C), and a second shallow-concave portion (14D). The first deep-concave portion (14A) and the second deep-concave portion (14C) are located so that effective cutting region of the cutting edge (17) is divided into three portions having lengths substantially equal to each other, and the second deep-concave portion (14C) is made deeper than the first deep-concave portion (14A). <IMAGE> |
