END MILL AND MANUFACTURING METHOD FOR THE SAME

摘要

PROBLEM TO BE SOLVED: To provide an end mill that when rotated, can improve defect resistance in a fast-moving outer periphery side and reduce cutting resistance in a slow-moving shaft line side so as to cut even an object with a small diameter of 2 mm or less keeping stable strength, thereby improving cutting performance and realizing long service life.SOLUTION: In a ridge line part between a cutting face 14 and a flank face 16 of a bottom blade 13 is formed a honing face 17 with a convex circular cross section that is 2 mm or less in diameter and orthogonal to the longitudinal direction of the ridge line part, and a curvature radius R of the honing face 17 is formed to gradually increase while going toward the outside in a radial direction.