Investigation of the parameter space for enhanced tool life in high aspect-ratio full-slotting micromilling of copper

This paper presents a preliminary investigation into the dependence of tool life on cutting parameters for high aspect-ratio full-slotting micromilling of copper under flood-like cutting fluid application. Full-slotting cutting tests were performed with a high aspect-ratio 100 μm diameter two-flute microendmill necked to 600 μm. Feedrate and axial depth of cut were varied between tests, with other parameters held constant, and tool life until tool break measured. The relationship between cutting parameters and tool life is examined in terms of three different methods for quantifying tool life: cutting time, final length of cut, and volume of material removed. It is found that the relationship between tool life and cutting parameters depends on the method employed to quantify tool life. An analysis of variance is performed on the collected tool life data to determine the relative significance of each parameter on tool life. It is found that the percentage of variance in tool life data which can be attributed to parameter variations is small when tool life is measured in length of cut or cutting time, but is significant when tool life is measured in volume of material removed. This suggests that determination of cutting parameters for improved tool life in micomilling can be better accomplished by measuring tool life as volume of material removed. It is found that when tool life is measured in this way, preferred parameters for enhanced tool life can be determined.