409L is a titanium-stabilized 11% chromium ferritic stainless steel (EN 1.4512, JIS SUH409L, GB 06Cr11Ti) — the standard material for automotive exhaust systems worldwide. It resists oxidation up to 550–650 °C, welds without sensitization cracking, forms well for tube drawing, and costs roughly half of 304 stainless. Nikasteel supplies 409L coil, sheet and strip with EN 10204 3.1 MTC — MOQ 5 t, FOB/CIF.
409L is the workhorse of the stainless exhaust industry: muffler tubes, catalytic converter shells, heat shields and tailpipes. It sits deliberately low on chromium (11%) with titanium added — enough for exhaust-temperature oxidation resistance, low enough on alloy content to keep the price close to carbon steel. This page collects the specification data buyers need before requesting a quote.
Equivalent Grades Across Standards
| Standard | Designation | Notes |
|---|---|---|
| EN 10088-2 / 10088-3 | 1.4512 — X2CrTi12 | European equivalent |
| JIS G3463 / JIS Z | SUH409L | Japanese automotive exhaust standard |
| GB/T 20878 (China) | 06Cr11Ti (old 0Cr11Ti) | Chinese mill production standard |
| UNS (USA) | S40970 (409Cb variant) / S40910 | ASTM A240 covers 409 family |
| KS (Korea) | ST409L | Used by Korean steelmakers |
Chemical Composition (typical ladle, %)
| C | Si | Mn | Cr | Ti | P | S | N |
|---|---|---|---|---|---|---|---|
| ≤ 0.030 | ≤ 1.00 | ≤ 1.00 | 10.5–11.7 | 6×C–0.75 | ≤ 0.040 | ≤ 0.020 (often ≤0.010) | ≤ 0.030 |
The "L" means extra-low carbon (≤0.03%), and titanium ties up residual carbon and nitrogen — together they prevent chromium carbide precipitation at welds (sensitization), the classic rust-along-the-weld failure.
Mechanical Properties (cold-rolled sheet, annealed)
| Property | Typical Value | Note |
|---|---|---|
| Yield strength Rp0.2 | ≥ 175–210 MPa | higher after skin pass |
| Tensile strength Rm | ≥ 360–460 MPa | — |
| Elongation A | ≥ 22–25% | good for cold forming |
| Density | 7.7 t/m³ | slightly below austenitics |
| Max service temp (oxidation) | 550–650 °C | intermittent up to ~750 °C |
Where 409L Is Used
- Automotive exhaust: intermediate pipes, muffler bodies, tailpipes, catalytic converter shells and heat shields — the dominant grade in OEM and aftermarket exhaust supply chains.
- Truck & motorcycle exhausts: same temperature service, cost-driven.
- Transformer housings & automotive trim: where mild corrosion resistance plus paintability is enough.
- Water heater anodes & domestic boiler parts: mildly corrosive hot water service.
If your parts face chlorides (road salt splash zones, coastal), jump to 439 or 436 ferritics — same family, better pitting resistance. See the full stainless cross-standard chart →
Weldability in Practice
- Welds by TIG, MIG, plasma and laser without preheat; titanium stabilization controls HAZ corrosion.
- For exhaust tube mills: TIG/laser welded then bead-rolled and seam-annealed — standard 409L tube route.
- Filler: usually autogenous (no filler) or 409Nb/309L for higher service temperature.
- Grain growth in the HAZ is inherent to ferritics — keep heat input moderate for fatigue-critical parts.
Supply from Nikasteel
We export 409L as hot-rolled coil (2.0–6.0 mm), cold-rolled coil/sheet (0.4–3.0 mm) and mill-edge or slit strip for tube mills, in standard mill widths or your slit widths. Every shipment carries EN 10204 3.1 mill test certificates; SGS/BV inspection can witness testing before shipment. Recent shipments include 409L + 304H in consolidated containers to Haiphong (Vietnam) — mixed grades in one container are welcome.
Need 409L coil, sheet or strip?
Send your thickness, width and tonnage to [email protected] or WhatsApp +86 191 5745 8011 — dated FOB/CIF quotation with 3.1 MTC, MOQ 5 tons.
Request a 409L Quotation