Hollow shafts can achieve torsional strength matching solid shafts by equating their twisting moments. Shafts manufactured via _____________ contain internal residual stresses?
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Answer: B. Cold rolling
Explanation
Cold rolling deforms metal below its recrystallization temperature, inducing severe localized mechanical strain. This non-uniform plastic deformation creates high internal stresses trapped within the metallic crystal lattice. As a result, shafts manufactured via cold rolling contain significant internal residual stress fields. Recrystallization eliminates strain hardening and internal residual stresses when heating above threshold. Residual stresses can either benefit or harm component performance depending on their stress state orientation. Torsional strength can be equated between solid and hollow shafts by analyzing geometric polar moments.
Transmission shafts produced by cold drawing or rolling require careful stress relief to prevent warping. Internal residual stresses can cause unexpected dimensional distortion during subsequent machining operations. Engineers account for built-in stresses when designing shafts for high-reliability aerospace applications. Forging at elevated temperatures allows recovery and recrystallization, minimizing trapped internal residual stresses. Hot rolling occurs above recrystallization temperatures, allowing thermal relaxation of internal mechanical stresses. Casting creates thermal contraction stresses rather than cold working plastic deformation residual stresses.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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