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1.3243

HS6-5-2-5

1.3243 (HS6-5-2-5) is a cobalt-alloyed [[glossary:schnellarbeitsstahl|high-speed steel]]: 6 % [[element:W|tungsten]], 5 % [[element:Mo|molybdenum]], 2 % [[element:V|vanadium]], and 5 % [[element:Co|cobalt]]. The cobalt boosts [[glossary:warmhaerte|hot hardness]] further — the steel still cuts at the highest cutting-edge temperatures where normal HSS gets soft. Applications: high-performance milling cutters, drilling tools for hard-to-machine materials.

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