Guest's failure criterion is specifically suited for evaluating the following category of materials_________________?
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Answer: B. ductile
Explanation
Guest's failure criterion is based on the maximum shear stress theory of elastic material breakdown. Ductile materials yield primarily through slip along planes of maximum shear stress under applied loads. This makes the maximum shear stress criterion the most accurate and suitable theory for evaluating ductile metals. Failure theories provide mathematical models to predict when complex multi-axial stresses will cause permanent yielding. Ductile materials exhibit significant plastic deformation before fracturing, unlike brittle materials which fail suddenly. Guest's criterion states that yielding begins when the maximum shear stress reaches half the tensile yield strength.
Mechanical engineers use Guest's theory to design safe shafts, pressure vessels, and structural steel components. Machine design software incorporates maximum shear stress calculations to evaluate ductile metal safety factors. Understanding material classification ensures engineers apply the correct failure theory for safe structural designs. Brittle materials are evaluated using maximum normal stress theories rather than shear-based yield criteria like Guest's. Elastic describes the temporary deformation phase rather than a specific material category evaluated by failure criteria. Plastic describes post-yield material behavior rather than the classification of materials suited for Guest's theory.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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