"The second step—**reducing cast iron’s high carbon content and producing steel—takes place in a BOF** (basic oxygen furnace; the adjective refers to the chemical properties of the produced slag). "The process was invented during the 1940s and was rapidly commercialized after the mid-1950s. Today’s BOFs are large, pear-shaped vessels with an open top used to charge up to 300 tons of hot iron, which gets blasted with oxygen blown in from both top and bottom. **The reaction reduces the metal’s carbon content** (to as little as 0.04 percent) **in about 30 minutes**. **The combination of a blast furnace and a basic oxygen furnace is the basis of modern integrated steelmaking**. "Final steps include the **transfer of hot steel to continuous casting machines to produce steel slabs, billets** (square or rectangular shapes), **and strips** that are eventually converted into final steel products." ([Location 1891](https://readwise.io/to_kindle?action=open&asin=B08SGC3TD3&location=1891)) --- **Tags** -- [[quotes]], [[steel]], [[basic-oxygen-furnaces]], [[iron-ore]], [[hot-briquetted-iron]], [[manufacturing]], [[steelmaking]], **Source** -- [[202412030828 - B - How the World Really Works]]