What steel is
Steel is an alloy of iron with less than 2% carbon, plus small amounts of manganese, silicon, phosphorus, sulphur and oxygen. There are more than 3,500 different grades1. What changes between them is the carbon and the elements added on purpose.
| Family | What sets it apart | How it behaves |
|---|---|---|
| Carbon steel | Iron and carbon with no added alloys. As a usual reference, low carbon is below 0.30%, medium between 0.30% and 0.60%, and high above that | More carbon means harder and stronger, and less ductile and weldable |
| Alloy steel | Contains added nickel, chromium, molybdenum or manganese. ReMA calls scrap "unalloyed" with residuals up to 0.45% Ni, 0.20% Cr, 0.10% Mo and 1.65% Mn2 | More strength, toughness or wear resistance depending on the alloy |
| Stainless steel | At least 10.5% chromium1. The 300 series (304, 316) contains nickel; the 400 series (430) does not | Chromium forms a passive layer that protects it from corrosion. The 300 series barely responds to a magnet |
| Cast iron | More carbon than steel (above 2%) | Brittle; it is cast in moulds instead of rolled. It is bought separately as cast scrap |
Two properties explain why steel scrap is so easy to recover: it is magnetic, so an electromagnet separates it from plastics and non ferrous metals3, and it is dense, so it is loaded and moved in large volumes.
A permanent material
worldsteel describes steel as a permanent material: it is recycled again and again without losing its properties1. The bar that leaves a furnace today can hold atoms from a rail, a car and a beam from decades ago.
- 90%of the steel in end of life cars is recovered 1
- 90%of the steel in machinery is recovered 1
- 85%of the steel in construction is recovered 1
- 30%recycled steel is the average content of a new steel product 1
In 2022 the world steel industry recycled between 650 and 700 million tonnes of scrap1. Steel products last 40 years on average, from weeks in packaging to more than two centuries in a building3, so the scrap available grows with the steel used in the past.
How steel is made
There are two main routes. The blast furnace with basic oxygen furnace (BF-BOF) starts from iron ore and coal. The electric arc furnace (EAF) melts mostly scrap with electricity and can run on 100% scrap, while an oxygen converter takes up to about 30%1.
| Route | Iron ore | Coal | Limestone | Scrap |
|---|---|---|---|---|
| Blast furnace and converter | 1,370 kg | 780 kg | 270 kg | 125 kg |
| Electric arc furnace | 586 kg | 150 kg | 88 kg | 710 kg |
The electric furnace is also fed with direct reduced iron (DRI), which dilutes residuals when the scrap available is not clean enough4.
Mexico melts scrap
Worldwide, 30.3% of crude steel was made in electric furnaces in 2025. In Mexico it was 95.9% of 13.5 million tonnes, which makes the country one of the producers most dependent on scrap5. CANACERO reports that 96.7% of national output comes from electric arc furnaces6.
- 13.5 Mtof crude steel produced in Mexico in 2025, 15th in the world 5
- 95.9%of that steel was made in electric furnaces 5
- 1.6 Mtof ferrous scrap exported by Mexico in 2025 5
- 1.4 Mtof ferrous scrap imported by Mexico in 2025 5
Every tonne of scrap that stays in the country and reaches a Mexican mill well graded is raw material that does not have to be imported. See the environmental impact of recycling it.
Where scrap comes from
Home scrap
Recovered inside the mill itself, for example in rolling. It never reaches the market3.
New or prompt scrap
Generated when steel products are made: stamping offcuts, turnings, rejected parts. The most valuable because it is concentrated and clean3.
End of life scrap
From dismantled goods: cars, buildings, ships, machinery. The most abundant and the most varied, with more traces of other elements3.
Ferrous scrap grades
The market uses the ReMA (formerly ISRI) specifications circular as its common language. Each grade sets thickness, maximum size, density and cleanliness2. These are the most common.
| Grade | ReMA code | What it is |
|---|---|---|
| HMS 1 (heavy melting steel 1) | 200, 201, 202 | Steel 1/4 inch (6.35 mm) thick or more, in pieces up to 5 by 2 feet |
| HMS 2 (heavy melting steel 2) | 203 to 206 | Steel 1/8 inch or more, black or galvanised |
| HMS 1&2 80:20 | No code of its own | A commercial blend of grades 200 to 206; a market convention, not a ReMA grade |
| No. 1 Busheling | 207 | Clean new factory clippings, uncoated, up to 2 by 5 feet |
| No. 1 and No. 2 bundles | 208, 209 | Sheet compressed to at least 75 pounds per cubic foot |
| Shredded | 210, 211 | Mixed and auto scrap shredded and magnetically separated |
| Plate and structural | 231, 232, 236 to 238 | Clean plate and sections 1/4 inch or more, cut to size |
| Machine shop turnings | 219, 220, 221 | Steel turnings and chips, without excessive oil |
| Iron borings | 223 | Clean cast iron borings and drillings |
| Cupola and machinery cast | 252, 261 | Clean cast iron pieces, furnace sized |
| Stainless 18-8 (type 304) | Sabot (solids), Ultra (turnings) | At least 7% nickel and 16% chromium |
Stainless 316 and 430 have no grade of their own in the circular: they are traded by description or chemical analysis2. To see what your material is worth, see how we build the offer.
What lowers the value of a load
- Copper and tin. They cannot be removed in the furnace. Above 0.1% copper, steel cracks when hot rolled, and tin makes it worse4. That is why motors, cable and bronze parts are separated first.
- Dirt, plastic, rubber and wood. Every grade must be free of dirt, non ferrous metals and foreign material2; anything that is not steel is paid as loss.
- Oil. Turnings must come without excessive oil2: draining them before loading improves the price.
- Out of grade size and thickness. A piece larger than the furnace charging box needs cutting, and thin sheet mixed with heavy scrap lowers density.
- Excessive rust. Rust is iron that no longer yields as metal2.
- Closed containers. They can explode in the furnace. They are cut and cleaned first, or not accepted.
Frequently asked questions
Is recycled steel as good as new steel?
Yes. Steel recycles without losing its properties1. What matters is the chemistry: the mill blends scrap to reach the composition each product needs.
How do I know if my material is stainless?
A quick test is a magnet: 300 series stainless barely sticks, although cold working can make it slightly magnetic. To know the exact series, a spectrometry analyser is used.
What is HMS?
Heavy Melting Steel. HMS 1 is steel 1/4 inch thick or more and HMS 2 is 1/8 inch or more2.
Why is scrap with copper paid less?
Because copper does not come out in the furnace and above 0.1% it cracks steel during rolling4. The mill has to dilute it with clean scrap or direct reduced iron.
Sources
Every figure on this page comes from a third party publication. Names and logos belong to their owners and only identify the source; they do not imply endorsement.
- World Steel Association (worldsteel)#SteelFacts, June 2026 update (2026)Open the publication
- Recycled Materials Association (ReMA)ReMA's ISRI Specifications Circular, Ferrous Scrap Guidelines (FS-2023) (2026)Open the publication
- World Steel Association (worldsteel)Raw materials: scrap (2026)Open the publication
- Environmental Science & Technology (ACS)Daehn, Cabrera Serrenho and Allwood, How Will Copper Contamination Constrain Future Global Steel Recycling?, 51(11):6599 a 6606 (2017)Open the publication
- World Steel Association (worldsteel)World Steel in Figures 2026 (2026)Open the publication
- Cámara Nacional de la Industria del Hierro y del Acero (CANACERO)Acero en cifras (2026)Open the publication
