(d) The yield strength values of pure aluminium (Al) and pure copper (Cu) are 25 MPa and 20 MPa, respectively; whereas the yield strength values of cold rolled Al-Mn-Mg alloy and cast 60-40 Brass (60% Cu, 40% Zn) are 200 MPa and 105 MPa, respectively. With aid of schematics, explain the main mechanisms account for the increases in the strengths. (e) A cylindrical tie rod with a diameter of 18.4 mm is subjected to cyclic loading. The stress range is +/- 200 kN. Figure Q3.3 shows the S-N curve of the material of which the rod is made, how many cycles will this rod survive? Stress amplitude J. (MPa) 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 10² 103 104 4340 low-alloy steel Stress ratio= -1 105 106 Number of cycles to failure, Nf 107 108

(d) The yield strength values of pure aluminium (Al) and pure copper (Cu) are 25 MPa and 20 MPa, respectively; whereas the yield strength values of cold rolled Al-Mn-Mg alloy and cast 60-40 Brass (60% Cu, 40% Zn) are 200 MPa and 105 MPa, respectively. With aid of schematics, explain the main mechanisms account for the increases in the strengths. (e) A cylindrical tie rod with a diameter of 18.4 mm is subjected to cyclic loading. The stress range is +/- 200 kN. Figure Q3.3 shows the S-N curve of the material of which the rod is made, how many cycles will this rod survive? Stress amplitude J. (MPa) 1500 1400 1300 1200 1100 1000 900 800 700 600 500 400 10² 103 104 4340 low-alloy steel Stress ratio= -1 105 106 Number of cycles to failure, Nf 107 108

Elements Of Electromagnetics

7th Edition

ISBN:9780190698614

Author:Sadiku, Matthew N. O.

Publisher:Sadiku, Matthew N. O.

ChapterMA: Math Assessment

Section: Chapter Questions

Problem 1.1MA

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