说明:1.刀具特点:(1)两切削刃刃背磨薄,横断面呈扁平状,以利排屑,冷却充分,减少轴向力。(2)修磨前面,使前角自外园至中心趋于一致(～20°)改善了外园处钻刃强度。(3)修磨横刃及顶尖处,刃后面磨月牙槽,使顶尖处呈 W 形,变横刃刮削、挤压为 Description: 1. Tool features: (1) two cutting edge grinding back thin, cross-section was flat to facilitate chip removal, cooling sufficient to reduce the axial force. (2) Sharpening the front so that the rake angle is uniform from the outer garden to the center (~ 20 °) improves the strength of the outer blade at the outer garden. (3) Sharpening the chisel edge and the top, grinding the alveolus behind the blade so that the top of the w-shaped, variable chisel scraping, squeezing