Frequently the S-N curves for steel can be approximated by a straight line between N=102 and N= 10° cycles when the data are plotted on a log-log scale as shown in the figure for SAE 4140 steel. This implies that S=ANh, where A and b are 7. constants. A. Find b for the 4140 steel for a certain part made from 4140 steel (Figure 17.33). B. Fatigue failures occur after 5 years. By what factor would the cyclic stress amplitude have to be reduced to increase the life to 10 years? Assume the number of cycles of importance is proportional to time of service.

Frequently the S-N curves for steel can be approximated by a straight line between N=102 and N= 10° cycles when the data are plotted on a log-log scale as shown in the figure for SAE 4140 steel. This implies that S=ANh, where A and b are 7. constants. A. Find b for the 4140 steel for a certain part made from 4140 steel (Figure 17.33). B. Fatigue failures occur after 5 years. By what factor would the cyclic stress amplitude have to be reduced to increase the life to 10 years? Assume the number of cycles of importance is proportional to time of service.

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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