The mechanical property allowing a material to withstand fracture under severe impact blows is referred to as__________________?
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Answer: D. toughness
Explanation
Toughness is the mechanical property that enables a material to absorb energy before fracturing. Materials with high toughness undergo plastic deformation rather than shattering under severe impact. This property combines both strength and ductility to resist sudden dynamic shock loads. Impact testing measures the energy absorbed by a notched sample during sudden fracture. Brittle materials lack toughness and fail abruptly when subjected to sharp impact blows. Heat treatment can optimize the balance of hardness and toughness in structural steels.
Mining machinery and construction equipment require tough materials to withstand severe impacts. Railway couplings and striking tools must resist fracture under heavy dynamic shock loading. Engineers select tough alloys to ensure structural components deform safely rather than breaking. Elasticity describes temporary deformation and energy recovery without permanent shape change. Endurance relates to fatigue resistance under repeated cyclic loading rather than single impacts. Strength measures resistance to static loads, whereas toughness specifically handles impact shocks.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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