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Byline: Daniel Iliescu, Daniel Gehin, Mohammed Nouari, Franck Girot Damage mechanisms of tipped tungsten carbide tools have been investigated when dry machining of multi-directional carbon fibre composites. The objective of this study is to determine the effects of the cutting parameters on the tool-workpiece interface and to identify the different wear modes. Different rake angles (0, 15 and 30), and feed rates (0.05, 0.1 and 0.2 mm/rev) were tested for a constant cutting speed (60 m/min). The cutting loads were determined, and the tool surface topography was analysed using complementary techniques. All aspects of material removal were found to be primarily dependent on the fibre orientation.

Byline: M.B. Cai, X.P. Li, M. Rahman Unlike in conventional cutting processes, where the undeformed chip thickness is significant compared to the cutting tool edge radius, in nanoscale cutting processes, the undeformed chip thickness is very small, on the nanoscales. Therefore, the tool edge radius can not been ignored. It has been found that there is a brittle-ductile transition in cutting of brittle materials when the cutting tool edge radius is reduced to nanoscale and the undeformed chip thickness is smaller than the tool edge radius. In order to better understand the mechanism of the transition, a molecular dynamics (MD) method, which is different from continuous linear mechanics, is employed to model and simulate the nanoscale ductile mode cutting process of monocrystalline silicon wafer. The simulated variation of the cutting forces with the tool cutting edge radius is compared with the results of the cutting force from experimental cutting tests and they show a good agreement. In the simulated results, it can be seen that the thrust force is much larger than the cutting force in cutting. The simulated results also denote that the resultant force in the cutting process is not uniformly distributed along the cutting tool edge. In the simulation, the elastic springback of small thickness is observed on the machined workpiece surface.

Byline: N. Geren, M. Bayramoglu, T. Tunc The water jet machine (WJM) tool is quickly gaining industrial acceptance for cutting nearly all types of materials into complex shapes. However, the high cost of these systems restricts their use by small and medium scale industries. The intensifier is the key unit of the WJM and significantly affects the cost of a WJM. Therefore, the present work aims to develop an intensifier for a low-cost WJM by applying reverse engineering and redesign methodology. The paper particularly concentrates on the design of high pressure components which require shrink-fitted assembly. The use of redesign technique together with the equations derived for this work have simplified the design of shrink-fitted parts and helped to minimise the time taken for the design of WJM intensifier. The design procedure used in this work not only simplifies the design, but also eliminates the re-machining requirement which is generally required to bring the inner radius of the intensifier to its desired size after the shrink-fit.