Q1/Create an estimated (S-N) diagram and define its equation for an axial fully reversed loaded steel bar. Its cross section shown in figure (1). Determine the life in cycle that can be expected if the alternating stress is (127Mpa). The bar surface finch is hot rolled. The operating temperature is (506 Co) and (du-577 Mpa). 120 mm. 4

============ Q1/Create an estimated (S-N) diagram and define its equation for an axial fully reversed loaded steel bar. Its cross section shown in figure (1). Determine the life in cycle that can be expected if the alternating stress is (127Mpa). The bar surface finch is hot rolled. The operating temperature is (506 Co) and (Out = 577 Mpa). 120 mm 4 Q2/A cantilever beam, shown in figure (2), is to be made from [Wrought-Aluminum Alloys- 3003- cold rolled]. If the desired design factor is (N=2.5), (P=4kN), and (F=6kN). Using a suitable failure theory, find the appropriate beam thickness h. P D=15cm d d=100mm F r=20mm L= 25 cm Q3/ a steel plate shown in figure (3): Sut=689 Mpa, reliability is 90%, factor of safety is 2, the size factor is 0.87. machined surface. Determine the plate thickness (t) for infinite life. Note: All dimensions are in mm. P= ± 50 kN <-100 Fig. 3 177 5r P = ± 50 kN 50

QUZ/ Create an estimated (S-N) diagram and define its equation for an axial fully reversed loaded steel bar. Its cross section shown in figure (1). Determine the life in cycle that can be expected if the alternating stress is 121.231 Mpa. The bar surface finch is hot rolled. The operating temperature is 503 Co and out = 598.954 Mpa. h= 148.929 mm b= 148.929 mm Fig. 1

QUESTION 2 Using the maximum-shear-stress (MSS) theory determine the factor of safety for a bar of AISI 1020 cold-drawn steel, see Table A-20) with the follwoing stresses: OX = 204 MPa, oy = -134 MPa