Study of tool life by breakage in micro-end-milling

Abstract

To obtain knowledge useful to predict the tool life due to breakage, a series of slotting experiments was performed at various feed rates for medium carbon steel using coated carbide square end-mills 0.5 mm in diameter. The main results obtained were as follows. (1) There is a possibility of obtaining an optimum feed rate for the maximum slotting distance. (2) Lower feed rate causes chatter but higher feed rate rarely causes chatter. (3) Minor's law based on the S-N curve of bending rotating fatigue tests was not applicable because the cumulative damage deviated widely. (4) Newly defined cumulative damage seems to be useful to some extent to predict tool life by monitoring cutting force.