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1.1645

C105W1

1.1645 (C105W1) is the old DIN designation for the unalloyed [[glossary:kaltarbeitsstahl|tool steel]] with 1.05 % [[element:C|carbon]] — today C105U (1.1545). The hardest of the unalloyed tool steels: peak [[glossary:haerte|hardness]], but brittle. Use: cutting tools, files, dies, razors.

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