Stress concentration effects under static loading conditions are_________________?
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Answer: A. very serious in brittle materials and less serious in ductile materials
Explanation
Brittle materials cannot redistribute high local stresses through plastic deformation under static loads. Stress concentration peaks remain unmitigated in brittle materials, rapidly initiating catastrophic cracking. Ductile materials safely blunt these stress peaks by localized yielding and micro-plastic flow. Geometric discontinuities like sharp corners disrupt internal stress trajectories and cause severe stress risers. Brittle fracture is characterized by rapid crack propagation perpendicular to principal tensile stress. Ductile metals absorb local strain energy without fracturing due to their extensive plastic range.
Designing machine components requires smooth transition fillets to protect brittle cast iron parts. Failure analysis often reveals that static cracks in brittle brackets originate at sharp notches. Understanding material ductility prevents catastrophic structural collapses in heavy engineering applications. Ductile materials are less sensitive because yielding relieves dangerous local stress concentrations. The seriousness of stress concentration is distinctly unequal between brittle and ductile materials. Outcomes are well understood and depend primarily on material ductility rather than random factors.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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