Stainless Steel 1.4547 vs 1.4462
EN 1.4547 stands out for its superior corrosion resistance, especially in highly aggressive environments, making it ideal for the most demanding applications. EN 1.4462, while also highly resistant to corrosion, is typically used in moderately corrosive environments where its excellent mechanical properties and good weldability are highly valued.
EN 1.4547 stainless steel (UNS S31254 / 254SMO)
Chemical Composition:
- High molybdenum content (6%)
- Higher nickel (18-20%) and chromium (19-20%) contents
- Additions of nitrogen (0.18-0.22%) and copper (0.5-1.0%)
Key Properties:
- Corrosion Resistance: Exceptionally high, Duplex 2205 Plate particularly against chloride-induced stress corrosion cracking, pitting, and crevice corrosion. Suitable for harsh environments, such as seawater applications.
- Strength and Toughness: Higher yield strength compared to standard austenitic grades. Maintains excellent toughness at both high and low temperatures.
- Weldability: Good, but requires specific procedures to avoid hot cracking and to maintain corrosion resistance.
EN 1.4462 stainless steel (UNS S31803 / S32205)
Chemical Composition:
- Moderate molybdenum content (3-3.5%)
- Nickel (4.5-6.5%) and chromium (21-23%) contents
- Nitrogen (0.08-0.2%) for added strength
Key Properties:
- Corrosion Resistance: Good, with excellent resistance to stress corrosion cracking, pitting, and crevice corrosion in moderately aggressive environments. Not as resistant as 254SMO stainless steel plate in highly corrosive conditions.
- Strength and Toughness: High yield strength, almost double that of conventional austenitic stainless steels. Good toughness, though slightly less than 6MO UNS S31254, particularly at very low temperatures.
- Weldability: Very good, with less risk of hot cracking compared to higher alloyed grades. Common welding techniques can be used.
How to choose: 1.4547 vs 1.4462 ?
For applications involving extreme conditions, such as seawater exposure or chemical processing with highly corrosive substances, EN 1.4547 is the better choice. In contrast, for applications that require high strength and durability in less aggressive environments, EN 1.4462 is often preferred due to its cost-effectiveness and sufficient performance.
