409
Data verified409 is a titanium-stabilised 11% chromium ferritic stainless developed for automotive exhaust systems. It offers enough oxidation and corrosion resistance for exhaust service at the lowest cost of any stainless family member.
Chemical composition
| Element | Content (%) |
|---|---|
| C | ≤0.08 |
| Si | ≤1.00 |
| Mn | ≤1.00 |
| P | ≤0.045 |
| S | ≤0.045 |
| Cr | 10.50–11.75 |
| Ni | ≤0.50 |
| Ti | 6×C–0.75 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Delivery condition | Annealed |
| Hardness | ≤183 HB (annealed) |
| Tensile strength | 380–550 MPa |
| Density | 7.70 g/cm³ |
| Magnetic | Yes |
Heat treatment
Anneal 790–870 °C, air cool. Titanium stabilisation prevents sensitisation in thin welded sections.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 1.4512 |
| aisi | 409 |
| jis | SUS409L (close) |
| gb | 06Cr11Ti |
Compare side by side: 409 vs 410L · 409 vs 430
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Automotive exhaust tubing, mufflers and catalytic converter shells, furnace parts, agricultural equipment.
Processing: Formable and weldable in thin gauges; grain growth in welds limits use in thick sections; widely supplied as welded tube.
FAQ
- Why do exhaust systems use 409 instead of 304?
- Cost: 409 has no nickel and the lowest chromium of the stainless family, yet it survives hot exhaust gas and road splash well enough for the design life of a muffler system.
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Ask for a quotationVisit NasteelSource: ASTM A240 / EN 10088 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.