An aircraft flap actuator housing made of cast magnesium alloy ZAG3A-T4 with uniaxial yield strength σY = 14,000 psi. At the suspected critical point the calculated state of stress as shown in the figure.
a) Is yielding of this part expected according to the Maximum Shear Stress (Tresca) criterion? Justify your answer.
b) Is yielding of this part expected according to the Von Mises criterion? Justify your answer.
c) Compare the results of parts a and b and comment.