| 摘要 |
A throw-away insert enabling the use of a holder for a long period and having excellent chip discharging property. The throw-away insert (1) comprises a plurality of divided main cutting edges (4a) formed in approximately polygonal plate shapes, having a cutting face (2) on the upper surfaces and flanks (3) on the side faces, and having a main cutting edge (4) formed at crossed ridge parts between the cutting face (2) and the flanks (3) and divided by at least one groove part (5) formed in the surfaces of the flanks (3). Projections (6) are formed on the cutting face (2) correspondingly to the divided main cutting edges (4a). |
