O-1 Oil Hardening Tool Steel

AISI O-1 is an oil-hardening tool steel which may be hardened from fairly low temperatures with little size change. O-1 combines deep-hardening qualities with a fine-grained structure, affording good initial production runs, and good continued production after grinding.

Chemical Composition

Carbon 0.90%
Manganese 1.25%
Chromium 0.50%
Silicon 0.50%
Tungsten 0.50%

Typical Applications

Blanking Dies Engraving Tools
Forming Dies Gauges
Knives Shear Blades

O-1 is an easy-to-harden tool steel grade that can be used for many simple tool types and is commonly used for pins, gauges, slides and fixtures. O-1 is readily available in flat ground stock and drill rod for quick turn-around parts.

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