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World of Engineering
@engineers_feed
The most fun way to learn something new everyday.
参加 August 2015
68 フォロー中    3.5M ファン
Steel is approximately 99% iron. The remaining 0.02–2% is carbon, and that tiny fraction is what separates a material that bends from one that can hold up a skyscraper. More carbon: harder and stronger, but more brittle. Less carbon: softer and more ductile, but weaker. The entire history of metallurgy is the story of humans learning to control that 1%.
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