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ADVANCED MANUFACTURING PROCESSES Proff. Strano – Annoni – Demir SURNAME NAME PERSONAL ID Exam – 9th September 2022 Question n. 1 Which of the following laser component/function couple is given WRONG? o Yttrium aluminium garnet doped with neodymium ions – Active medium o Diode – Active medium o Bragg grating – Wavelength harmonic generator o Diode – Pumping medium o CO2+N2+He mixture – Active medium Question n. 2 Considering the motionless extended planar heat source during a laser heat treatment which of the following statements is CORRECT? o With a diode laser source it is easier to increase the temperature of gold compared to steel. o The cooling rate of steel can be increased by decreasing the power and increasing the pulse duration o It can be used to precisely estimate the time required to start evaporating the surface of a Ni-alloy o The model correctly estimates the temperature rise for all beam shapes. o At a given point below the surface, the maximum temperature can be reached after turning off the laser emission Question n. 3 Which of the following conditions is mandatorily required for a remote keyhole laser welding operation? o An inert gas protecting the melt pool o Irradiance greater than 106 W/cm2 o Beam wobbling o Filler wire o Presence of gap Question n. 4 What are the most important properties of a material suited for rapid tools for injection molding? (multiple answer are allowed) Does this tube require a preliminary bending operation? o High compression resistance o High temperature resistance o High UTS o Low glass transition temperature o All of the above o None of the above Question n. 5 Why should we consider the spindle power and torque diagram in micromilling? o None of the above o To calculate the workpiece roughness o To check if the spindle…