Exercises Varia

Varia. Exercises
16.1 Which of the following are bulk deformation processes (three correct answers): (a) bending, (b) deep drawing, (c)
extrusion, (d) forging, (e) rolling, and (f) shearing?
16.3 The flow curve expresses the behavior of a metal in which of the following regions of the stress-strain curve: (a)
elastic region or (b) plastic region?
16.6 Which of the following are advantages and characteristics of hot working relative to cold working (four correct
answers): (a) fracture of workpart is less likely, (b) friction is reduced, (c) increased strength properties, (d)
isotropic mechanical properties, (e) less overall energy is required, (f) lower deformation forces is required, (g)
more significant shape changes are possible, and (h) strain-rate sensitivity is reduced?
16.2 A metal has a flow curve with strength coefficient = 850 MPa and strain-hardening exponent = 0.30. A tensile
specimen of the metal with gage length = 100 mm is stretched to a length = 157 mm. Determine the flow stress at
the new length and the average flow stress that the metal has been subjected to during the deformation.
18.10 Which of the following are variations of sheet-metal-bending operations (two best answers): (a) coining, (b)
flanging, (c) hemming, (d) ironing, (e) notching, (f) shear spinning, (g) trimming, and (h) tube bending?
18.3 A compound die will be used to blank and punch a large washer out of 6061ST aluminum alloy sheet stock 3.50
mm thick. The outside diameter of the washer is 50.0 mm and the inside diameter is 15.0 mm. Determine (a) the
punch and die sizes for the blanking operation, and (b) the punch and die sizes for the punching operation.