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1.1520

C70U

1.1520 (C70U) is an unalloyed [[glossary:kaltarbeitsstahl|tool steel]] with 0.7 % [[element:C|carbon]]. Without any significant alloying elements, it is a [[glossary:wasserhaertung|water-hardening steel]]: it is quenched in water and hardens only on the surface layer — the core stays tough. Use: simple hand tools, chisels, hammers, pliers, knife blades, where [[glossary:randschichthaerte|surface hardness]] plus a tough core is needed.

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