Different types of stainless steel have different compositions. The same type of stainless steel may have variations due to the addition of trace elements.
These variations usually improve specific properties such as weldability, corrosion resistance, hardness, or processing performance by adjusting the carbon content or adding specific alloying elements to meet different application requirements.
They exhibit their strength, corrosion resistance, weldability, and magnetism characteristics, making them suitable for a wide range of industrial applications.
The diagram on the right shows the relationship between stainless steel grades.
Let’s continue learning about the element content of stainless steel.
Stainless Steel Composition Metallurgy Tree
Stainless Steel Composition
| Stainless Steel Type | Variant | Cr (%) | Ni (%) | Mo (%) | C (%) | Other Key Elements | Key Characteristics |
| Austenitic | 304 | 18-20 | 8-10.5 | / | ≤0.08 | / | Excellent corrosion resistance and formability, suitable for food processing, chemical industries, etc. |
| Austenitic | 304L | 18-20 | 8-12 | / | ≤0.03 | / | Low-carbon version of 304, less prone to intergranular corrosion during welding. |
| Austenitic | 304H | 18-20 | 8-10.5 | / | 0.04-0.10 | / | High-carbon version of 304, suitable for high-temperature environments, higher strength. |
| Austenitic | 316 | 16-18 | 10-14 | 2-3 | ≤0.08 | / | Increased molybdenum content, improved chloride corrosion resistance, suitable for marine environments and chemical processing equipment. |
| Austenitic | 316L | 16-18 | 10-14 | 2-3 | ≤0.03 | / | Low-carbon version of 316, better weldability, and corrosion resistance. |
| Austenitic | 316Ti | 16-18 | 10.5-14 | 2-3 | 0.04-0.10 | Ti: 0.5% | Titanium-stabilized, enhanced resistance to intergranular corrosion, suitable for high-temperature environments. |
| Ferritic | 430 | 16-18 | / | / | ≤0.12 | / | Good oxidation resistance and formability, suitable for home appliances, automotive trim, etc. |
| Ferritic | 430F | 16-18 | / | / | ≤0.12 | S added | Increased sulfur content, improved machinability, suitable for automatic lathes. |
| Ferritic | 409 | 10.5-11.75 | / | / | ≤0.08 | / | Economical stainless steel, good heat resistance, suitable for automotive exhaust systems. |
| Ferritic | 409L | 10.5-11.75 | / | / | ≤0.03 | / | Low-carbon version of 409, better weldability, suitable for automotive exhaust systems. |
| Martensitic | 410 | 11.5-13.5 | / | / | ≤0.15 | / | High strength and wear resistance, suitable for tools, bearings, etc. |
| Martensitic | 410S | 11.5-13.5 | / | / | ≤0.08 | / | Low-carbon version of 410, improved weldability and toughness. |
| Martensitic | 420 | 12-14 | / | / | 0.15-0.40 | / | Excellent polishing properties, suitable for surgical instruments, cutting tools. |
| Martensitic | 420J2 | 12-14 | / | / | 0.26-0.40 | / | Increased carbon content, higher hardness and wear resistance, suitable for tools, bearings. |
| Martensitic | 440C | 16-18 | / | / | 0.95-1.20 | / | Very high hardness and wear resistance, suitable for high-precision bearings, tools. |
| Martensitic | 440A | 16-18 | / | / | 0.60-0.75 | / | Lower carbon content, better corrosion resistance, suitable for tools and instruments. |
| Duplex | 2205 | 22-23 | 4.5-6.5 | 3-3.5 | ≤0.03 | / | High strength, excellent resistance to chloride stress corrosion cracking, suitable for marine and chemical processing applications. |
| Duplex | 2507 | 24-26 | 6-8 | 3-5 | ≤0.03 | / | Super duplex stainless steel, extremely high corrosion resistance and strength, suitable for oil, gas, and other extreme environments. |
| Precipitation Hardening | 17-4PH | 15-17.5 | 3-5 | / | ≤0.07 | Cu: 3-5%, Nb: 0.15-0.45% | High strength obtained through aging treatment, suitable for high-strength applications. |
| Precipitation Hardening | 15-5PH | 14.5-15.5 | 3.5-5.5 | / | ≤0.07 | Cu: 2.5-4.5%, Nb: 0.15-0.45% | Similar to 17-4PH, but with better toughness, suitable for applications requiring high strength and toughness. |
Why SSM is Your Trusted Supplier of Stainless Steel Products
Selecting the right stainless steel products for your project is a critical decision, and at SSM, we understand that it shouldn’t be left to chance. We go beyond being just a supplier – we are your reliable partner in providing stainless steel products.
Get in touch with us today for a free quote and experience the difference of partnering with true experts in metal excellence.
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