How is steel produced from phosphatic iron classified_________________?
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Answer: A. brittle
Explanation
High phosphorus content in iron makes the resulting steel cold-short and brittle. Phosphorus dissolves in ferrite and increases hardness while drastically reducing impact toughness. Phosphoric iron creates steel prone to cracking when worked at low temperatures. Steel metallurgy classifies phosphorus as an undesirable impurity in most structural grades. Cold-shortness refers to brittleness exhibited by steel at ordinary or low temperatures. Steelmaking refining processes use basic oxygen furnaces to remove excess phosphorus.
Structural steel manufacturers strictly limit phosphorus percentages to ensure impact safety. Building bridges and pressure vessels requires tough steel resistant to low-temperature brittle fracture. Controlling chemical impurities prevents catastrophic structural failures in engineering components. Hard does not capture the specific dangerous brittle failure mode caused by phosphorus. Ductile steel deforms under tensile stress, which contradicts phosphatic embrittlement. Tough steel absorbs impact energy without fracturing, unlike high-phosphorus brittle steel.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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