Fe, Steal지구상 가장 많은 질량 차지IronsStainlessSteel The Entire History of SteelFrom hunks of iron streaking through the sky, to the construction of skyscrapers and megastructures, this is the history of the world's greatest alloy.https://www.popularmechanics.com/technology/infrastructure/a20722505/history-of-steel/
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