Radius end mill having radius edge enhanced in resistance to chipping and fracture

摘要

In a radius end mill (REM) having a bottom edge (2) formed on the end face thereof, a radius edge (1) designed in a substantially quarter-circle arc shape and formed at a corner portion thereof, and an outer peripheral edge (3) formed spirally on the side surface thereof, the bottom edge (2) and the radius edge (1) being continuously connected to each other at a connecting point A while the radius edge is continuously connected to the outer peripheral edge (3) at a connecting point B, when a view taken along a plane that passes through the connecting points A and B and crosses a rake face of the radius edge is represented by an R cross-sectional view, the rake face (7) of the radius edge (1) is designed to have a convex curved line extending from the connecting point A to the connecting point B in the R cross-sectional view.