Design and performance analysis of TiCN-coated cemented carbide milling cutters

The Taguchi method was employed to analyze and optimize titanium carbonitride films of cemented carbide (WC-6%Co-10%TiC-8%TaC) indexable milling cutters regarding machining conditions. Six variables, i.e. film construction, cutting speed, feed rate, depth of cut, workpiece hardness and milling type, were considered. The results showed that the film construction was the most dominant variable, with a percentage contribution to the overall performance of the milling system as high as 46.10%. Through statistical calculation, an optimum variable combination was obtained, the optimal film construction being 3 μm TiCN + 2 μm TiCN (from the substrate to the top) rather than 5 μm TiCN alone. The resultant flank wear achieved 380 and 280% improvement compared with the uncoated and 5 μm TiCN-coated cutters.