Prestasi Pahat Karbida Berlapis pada Operasi Frais Bebas Cemar Bahan Paduan Titanium

Abstract

From a serial of machining trials that carried out in this study, it was obtained that carbide tool (WC+Co) coated with (TiC/TiAlN/TiN) by PVD method could be used to dry mill titanium alloy Ti-6Al-2Sn-4Zr-2Mo-0.08Si (Ti- 6242S) up to cutting speed (V) of 150 m/min, feeding (f) of 0.15 mm/tooth, axial depth-of-cut (aa) of 2 mm, and radial depth-of-cut (ar) of 8.8 mm. This cutting condition, in particular cutting speed, is 2.5 times higher than the common cutting speed used for cutting titanium alloys (60 m/min). Although under that cutting condition tool life was recorded as short as 1.70 minutes, but the round insert tool type used in this study could be indexed and thus, each insert had 5 cutting edges. As a result, the total tool life can be achieved by each insert tool is 8.5 minutes and this value is higher than the shortest tool life required for cutting of titanium alloys (5 minutes). The cutting conditions (cutting speed and feeding) and tool life are then formulated based on the Taylor model VTn =C dan fTn =C. The lower exponent value (n) in VTn =C model comparing to fTn =C model indicates that tool life is more effected by cutting speed than feeding.