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ADVANCED MANUFACTURING PROCESSES A Prof. Annoni SURNAME NAME PERSONAL ID Exam – 10th July 2024 Question n. 1 According to the lumped heat cap acity model applied to the laser cutting process, which of the following statements is TRUE? o The kerf width is always equal to the beam waist diameter of the laser beam o If the sheet thickness is increased the velocity must be increased proportionally o In the case material evaporation occurs the cutting speed must be reduced o The model allows to estimate the heat affected zone Question n. 2 Which of the following statements is TRUE regarding laser welding processes? o Fiber laser sources are always the preferred option o When performing butt joints it is preferable to have high gap between the sheets o A plume cutter allows to reduce plasma formation thus increasing the process stability o A higher beam quality factor generates lower beam waist diameter Question n. 3 Taking into account laser texturing processes, indicate which of the following statements is WRONG? o With pulsed wave lasers, higher emission power increases the ablation diameter o Shorter pulse durations allow to increase the peak emission power o The use of optics with longer focal length reduces the beam waist diameter o Both polishing and roughing operations can be performed Question n. 4 Considering the Laser Powder Bed F usion process (also known as Selective Laser Melting) indicate which of the following is TRUE: o Diode laser sources cannot be employed due to their elevated efficiency o Lack of fusion porosity is obtained at high levels of energy density o A scanner head with galvanometric mirrors is employed to deflect the beam along the intended trajectory o A vacuum chamber is typically employed to prevent oxidation of the material during processing…