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Course of ADVANCED MANUFACTURING PROCESSES Proff. Michele Monno – Barbara Previtali – Matteo Strano SURNAME NAME PERSONAL ID Exam September 11th 2015 Exercise n. 1 – scientific article comprehension Read the attached paper “Technological and Economical Comparison of Roughing Strategies via Milling, EDM and ECM for Titanium- and Nickel-based Blisks”. In addition to the information given in the paper, please consider that: • The current used in the EDM roughing tests with bot h the Roboform and the Eagle machines is I=32 Amp . • Calculate the specific removal rate for both the EC M and the EDM processes, when machining the Inconel 718. C EDM_roboform =__________ [mm 3/Amp/s] CEDM_eagle =__________ [mm 3/Amp/s] CECM =__________ [mm 3/Amp/s] • Calculate the current I and the current density J used by the authors when obtaining the data in Table 1 in ECM machining of Inconel 718. I = ___________ Amp J=___________ Amp/mm2 • Under the assumptions of the paper, the simplified gap with no undercuts is obtained by machining axially. The authors conclude that for more than 400 parts per year, ECM seems be more cost efficient technolo gy than EDM. How do you expect the main costs components for both EDM and E CM to change (increase, decrease, unchanged) if the simplified gap was obta ined with a radial rather than axial machining? 1 ECM EDM Investment costs machine hour rates and wage costs Tooling design and manufacturing costs 2 Exercise n. 2 – technological problem Your company produces supports out of thin inox steel plates. At the moment you have in house two different techno logies: a blanking machine and a laser cutting system. A customer ask you for a new job, consisting in the production of 8000 pieces of the component presented in Figure 1. The thickness of the initial…