By what metallurgical method can the tensile strength of steel be safely enhanced________________?
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Answer: C. adding carbon up to 0.83%
Explanation
The tensile strength and hardness of plain carbon steel increase as carbon content rises up to the eutectoid limit of zero point eight three percent. Adding carbon promotes the formation of hard cementite phases within the pearlite microstructure during controlled thermal cooling processes. Exceeding this specific eutectoid percentage introduces brittle proeutectoid cementite grain boundaries that degrade overall structural reliability. Plain carbon steels are iron-carbon alloys whose mechanical properties depend heavily on microscopic phase distributions and heat treatment. The iron-carbon phase diagram identifies zero point eight three percent carbon as the critical eutectoid composition point. Metallurgical processing uses controlled carbon additions to balance tensile strength, hardness, and ductility in manufactured steel.
Adding carbon up to two point eight percent pushes the alloy into cast iron territory, causing extreme brittleness and low tensile strength. Higher carbon percentages like six point three percent exceed steel solubility limits and form unusable, heavily degraded metal alloys. Adding small quantities of copper improves atmospheric corrosion resistance rather than functioning as the primary carbon strengthening method.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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