钢铁的主体元素是铁,铁在地壳的成分中占有很大比例,具有开采价值的铁矿也比较多,钢铁的用途又广,因此在金属中钢铁的产量是最大的。我们到处可以看到钢铁。横跨江河的大铁桥,成千上万公里长的铁轨,输送石油和天然气的钢管,建筑上的大屋顶的钢铁结构,高楼大厦、 Steel is the main element of iron, iron accounts for a large proportion of the composition of the earth’s crust, with more iron ore mining value, the use of steel is also wide, so the output of steel in the metal is the largest. We can see the steel everywhere. Large iron bridges across the river, thousands of kilometers of railroad tracks, oil and gas pipelines, large roof steel structures, skyscrapers,