A rectangular cross-section bar with a height h = 2 + (XY/50) in and a base b = 2 - (XY/200) in, in the orientation shown below, is subject to a completely reversed internal bending moment that cycles from + 70 kip-in to 70 kip-in at a service temperature of 750°F. The bar has a machined surface and has a 0.08 in. radius notch with the theoretical stress concentration of K, = 1.8. At room - temperature the strength of the steel is S₁t = 120 + (XY/3) kpsi. ut b=2(XY/200) in b 0.08 in notch radius h C M = ± 70 kip-in h=2+(XY/50) in a) With a 90% reliability estimate, the endurance strength of the part is at a temperature of 750°F. Hint: This is a rectangular cross-section in non-rotating bending. b) What is the fatigue strength of this part if it is to survive N = (55 + XY) * 10³ cycles at 750°F?

A rectangular cross-section bar with a height h = 2 + (XY/50) in and a base b = 2 - (XY/200) in, in the orientation shown below, is subject to a completely reversed internal bending moment that cycles from + 70 kip-in to 70 kip-in at a service temperature of 750°F. The bar has a machined surface and has a 0.08 in. radius notch with the theoretical stress concentration of K, = 1.8. At room - temperature the strength of the steel is S₁t = 120 + (XY/3) kpsi. ut b=2(XY/200) in b 0.08 in notch radius h C M = ± 70 kip-in h=2+(XY/50) in a) With a 90% reliability estimate, the endurance strength of the part is at a temperature of 750°F. Hint: This is a rectangular cross-section in non-rotating bending. b) What is the fatigue strength of this part if it is to survive N = (55 + XY) * 10³ cycles at 750°F?

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter5: Stresses In Beams (basic Topics)

Section: Chapter Questions

Problem 5.8.8P: A beam of rectangular cross section (width/) and height supports a uniformly distributed load along...

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