Description:
Stainless steel grade 409L is a general chromium, titanium stabilized, ferritic stainless steel whose primary application is automotive exhaust systems. It contains 11% chromium which is the minimum amount for the formation of the passive surface film which gives stainless steels their corrosion resistance. It combines good elevated temperature corrosion resistance with medium strength, good formability, and overall cost.
Stainless steel grade 409L resists corrosion strongly compared to carbon steel and is used as an alternative to carbon steel in mildly challenging environments where its high resistance to corrosion and high temperature oxidation gives an advantage. It is commonly used in applications where appearance is a secondary quality to mechanical properties and corrosion resistance.
Chemical Properties:
| C | Mn | Si | P | S | Cr | Ni | Ti | |
| 409L | max:0.03 | max:1.0 | max:1.0 | max:0.045 | max: 0.045 | min: 10.5 max: 11.75 | max: 0.5 | min: 0.48 max: 0.75 |
Mechanical Properties:
| Grade | Tensile Strength MPa (min) | Yield Strength 0.2% MPa(min) | Elongation % | Hardness (HB) MAX | Hardness (HRB) MAX |
409L | 380 | 207 | 20 | 207 | 95 |
Applications:
Although Alloy 409 is designed principally for the automotive exhaust industry, it has been successfully used in other industrial applications as well. Some examples of applications that call for Alloy 409 include:
Automotive exhaust systems
Catalytic converters
Mufflers
Tailpipes
Farm equipment
Structural support and hangers
Transformer cases
Furnace components
Heat exchanger tubing
