01 Ironmaking
Blast furnace or DRI turns ore + reductant into hot metal or sponge iron.
Steel · The iron–carbon workhorse of buildings, ships, rails and tools — endlessly recast.
Darker cells mean a higher score for this topic on that metric.
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As a metal it is Euroclass A1, but it loses yield in fire and usually needs protection for a rated duration.
Steel is iron with controlled carbon (typically <2%) and alloys; cast iron has more carbon and a different solidification path.
No. Thermal conductivity is tens of W/m·K. Insulation is a separate layer (mineral wool, boards, VIP).
Iron oxidises in the presence of water and oxygen. Alloys, zinc, paint or concrete cover slow that.
No. Chlorides, crevices and wrong grades pit. 304 vs 316 is a chemistry choice, not a slogan.
Magnetically, yes as a family. Copper contamination and coatings constrain some high-spec loops.
heat 72 · fire 84
Making Steel is a chain: feedstock, conversion (bloomery c. 1800 BCE / Bessemer 1856), forming, heat, finish, install.
Skip a step and the properties chapter is describing a different object.
Blast furnace or DRI turns ore + reductant into hot metal or sponge iron.
BOF or EAF adjusts carbon, phosphorus and alloys, then vacuum degasses if needed.
Continuous casters freeze slabs, blooms or billets.
Reheat and reduce to plate, strip, sections or rod.
Skin pass, anneal, quench-and-temper or galvanize.
Cut, weld, bolt, form — residual stress and HAZ hardness become the real spec.
Primary ore route; high CO₂ unless CCS or hydrogen later.
Mini-mills recycle steel with electricity; residual copper limits some grades.
Gas or hydrogen reduction plus arc furnace — the green-steel bet.
Cast steels and irons for complex shapes that rolling cannot make.
Feedstock to installed product.
Energy in, class out.
Plain carbon steel rusts unless coated, alloyed or kept dry.
A1 does not mean “safe in a blaze”; protection is a separate layer.
High carbon equivalents crack unless preheat and hydrogen control are real.
Process energy and scrap quality belong in the carbon passport, not in a footnote.
Light structural metal from Hall–Héroult cells — aircraft skins, cans and façades.
Overall 59 ✈️High specific strength and chloride-tolerant films — airframes, implants and seawater.
Overall 58 🔶The first industrial conductor — wiring, heat exchangers, roofs that go green.
Overall 57 🍴Chromium passive films that keep kitchens, chemical plant and façades from rusting like carbon steel.
Overall 64