III-A component is subjected to a cyclic loading at the frequency of once every 5 minutes for 5 years. The cycle is between 220 MPa in tension and 50 MPa in compression. The fracture toughness of the material is 80 MPa√m, Y = 1.12, C = 1.62 x 10-12 (MPa and m) and n = 3.2, and we know that it has initial cracks of length 0.1 mm. At the end of the 5 years, because of the failure of other components, the stresses become 10 times larger. Is the component able to hold the new cyclic loading? If so, for how long? If not, explain.

III-A component is subjected to a cyclic loading at the frequency of once every 5 minutes for 5 years. The cycle is between 220 MPa in tension and 50 MPa in compression. The fracture toughness of the material is 80 MPa√m, Y = 1.12, C = 1.62 x 10-12 (MPa and m) and n = 3.2, and we know that it has initial cracks of length 0.1 mm. At the end of the 5 years, because of the failure of other components, the stresses become 10 times larger. Is the component able to hold the new cyclic loading? If so, for how long? If not, explain.

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter2: Axially Loaded Members

Section: Chapter Questions

Problem 2.5.1P: The rails of a railroad track are welded together at their ends (to form continuous rails and thus...

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