A solid cylindrical shaft made of AISI 1020 steel (quenched and tempered at 870oC) rotates at a speed that produces a safety factor of 2.5 against the stress causing yielding. To instrument the shaft, a small hole is drilled in its center for electric wires. At the same time the material is changed to AISI 1080 steel that has been quenched and tempered at 800oC. Find the safety factor against yielding of the new shaft.

A solid cylindrical shaft made of AISI 1020 steel (quenched and tempered at 870oC) rotates at a speed that produces a safety factor of 2.5 against the stress causing yielding. To instrument the shaft, a small hole is drilled in its center for electric wires. At the same time the material is changed to AISI 1080 steel that has been quenched and tempered at 800oC. Find the safety factor against yielding of the new shaft.

Mechanics of Materials (MindTap Course List)

9th Edition

ISBN:9781337093347

Author:Barry J. Goodno, James M. Gere

Publisher:Barry J. Goodno, James M. Gere

Chapter3: Torsion

Section: Chapter Questions

Problem 3.7.12P

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