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1.0553

S355J0

The 1.0553 (S355J0) is a mild steel: easily weldable, inexpensive, and the workhorse of structural steel. The "S" means the guaranteed [[glossary:streckgrenze|yield strength]] in MPa — S355 holds at least 355 MPa. Typical analysis: 0.2 % C, 1.45 % Mn, 0.35 % Si. For higher [[glossary:verschleissschutz|wear protection]], three hard-facing options are available: S Fe 1 (martensitic, approx. 300–400 HB, machinable), S Fe 2 (wear-resistant and tough, approx. 50–55 HRC, conditionally machinable) and S Fe 15 ([[glossary:karbid|carbide]]-rich, approx. 55–65+ HRC, not machinable).

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