Railway track rails are conventionally manufactured from_______________?
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Answer: C. high carbon
Explanation
Railway track rails require high mechanical strength, hardness, and exceptional wear resistance during service. High carbon steel provides the necessary microstructural hardness to withstand heavy rolling wheel loads. Carbon content in rail steel typically ranges between 0.6 percent and 0.82 percent for optimal durability. Railroad tracks experience continuous cyclic loading, friction, and impact forces from heavy freight trains. Plain carbon steels are heat-treated to achieve pearlitic microstructures capable of resisting severe track wear. Metallurgical composition must balance strength and ductility to prevent sudden brittle fracture under traffic.
Railway networks rely on durable steel rails to ensure safe high-speed passenger and heavy freight transportation. Selecting appropriate track materials minimizes maintenance frequency and prevents catastrophic derailment accidents globally. Track engineers continuously monitor rail wear and metallurgical integrity across national transportation infrastructures. Mild steel lacks the necessary surface hardness and wears down too quickly under heavy train wheels. Alloy steels are used for specialized switches and crossings but are too costly for entire rail networks. Cast iron is too brittle and lacks the tensile strength required for modern structural railway tracks.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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