| In interrupted dry cutting, both sharp tools and blunt tools have short lives. The tool life decides the cost, tool changing frequency, and machining precision. Finding the proper edge radius, which leads to longer tool life, is an effective way to improve machining efficiency and quality. In this thesis, the tool-wear behavior of PVD coated High-Speed-Steel cutting tools with different cutting-edge radii have been experimentally investigated. By conducting fly hobbing tests, the optimum cutting-edge radius and edge-preparation process for coated HSS cutters have been concluded. Furthermore, the influence of cutting-edge radius on the performance of PVD-coated carbide inserts has also been investigated experimentally and numerically. The simulation results from DEFORM 3-D agree well with the experiment results from orthogonal cutting. Finally, some simulation results such as strain, strain rate and stress have been analyzed. The experimental and numerical investigations have provided guidelines and evidence for future study of the tool-wear behavior of PVD-coated carbide cutters in gear hobbing. |
