Ohio Flame · Buying Help
"Corten Steel" Fire Pits: Why Ohio Flame Doesn't Claim It
A lot of outdoor-steel manufacturers advertise "Corten steel" as a quality signal. Corten is actually a trademarked US Steel alloy from the 1930s, not available for retail purchase. Ohio Flame uses a comparable carbon-grade steel and is explicit about it — here's what the distinction actually means for your fire pit.
By Ash · Updated November 10, 2026
What you need
Step by step
Know what Corten actually is
Corten steel is a specific blend of steel alloys patented by US Steel in the 1930s. Known for corrosion resistance and tensile strength, it became popular for outdoor construction in the 1960s. Critical fact: the proprietary composition is ONLY available from US Steel in strip-mill plate and sheet form. It is not available to the public, and almost no outdoor-living manufacturer actually buys it from US Steel.
Identify the comparable alternatives
Closest comparable grades include A606 Type 4, A588, and A847. These weathering steels exhibit the same oxide-barrier corrosion protection mechanism. Any manufacturer using these grades is accurate to call the result a "weathering steel" — but calling it "Corten" without actually sourcing from US Steel is technically wrong.
Understand what Ohio Flame uses
Ohio Flame's steel is a carbon-grade American-sourced steel. It is NOT Corten. It exhibits a similar oxidation and weathering process that forms a protective oxide barrier, but Ohio Flame deliberately does not use the Corten name — they consider it misleading to customers.
Know how to verify steel claims
Ohio Flame's advice for any outdoor-steel purchase: ask for Material Test Reports (MTRs) and ask for actual thickness measured with a micrometer. "Corten" and "1/4-inch thick" are marketing terms that often don't survive a MTR check.
Common mistakes
- Paying a premium for a "Corten" fire pit that's actually A606. A606 is a legitimate weathering steel with similar performance, but it's not Corten. The real question isn't the name — it's the thickness, the grade of weathering steel, and the welds.
Hands-on tips
- If a competitor claims "Corten," ask for the MTR. If they can't produce one, it isn't Corten.
- Thickness matters more than alloy name for fire-pit durability. 1/4" of carbon steel outlasts 1/8" of Corten.
Questions people ask
Is Ohio Flame's steel worse than Corten?
No. It weathers via the same iron-oxide barrier mechanism and Ohio Flame warranties the bowl for lifetime. The Corten name doesn't change the underlying metallurgy.
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