O1 Steel Oil Hardening Tool Steel Bar With 1.2510 SKS3

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Heat Treatment
Cold Processing
Hot Working

DIN 1.2510 SKS3 O1 Oil Hardening Steel Bars Tool Steel

o1 steel Oil Hardening Steel Bars Tool Steel

1 O1 Steel Introduction:

O1 tool steel is a low alloy cold work tool steel that must be oil-quenched in heat treatment. O1 tool steel contains small amounts of manganese, tungsten, and chromium, giving O1 tool steel adequate toughness for normal tool & die uses. O1 tool steel has deep hardening properties with fine grain structure with unusual toughness. O1 tool steel has good response to heat treatment with small dimensional changes. Sizes over approximately 2 inches thick or round may exhibit a lower hardness in the interior. O1 tool steel is available in standard de-carb free rounds, flats and squares, as well as the largest size selection in ground flat stock and drill rod of all the tool steel grades.

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2 O1 Steel Applications:

Where greater dimensional stability in heat treatment or improved wear resistance is required, tool steels with higher alloy contents, such as A2 or D2 should be considered. Typical applications for O1 tool steel are Blanking Dies, Drawing Dies, Extrusion Dies, Form Cutters, Forming Dies, Gauges-Special, Lamination Dies, Master Tools, Molding Dies, Paper Knives, Precision Tools, Punches, Reamers, Roll Threading Dies, Screw Dies, Sub-Press Dies, Taps Trimming Dies, etc.

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3 Quality Standard:

ASTM A681 – 08 Standard Specification for Tool Steels Alloy.

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4 All Grades Comparison:

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5 O1 Steel Chemical Composition(%)

0.85-1.000.10-0.501.00-1.400.030 max0.030 max0.40-0.700.030 max0.40-0.60

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  • FORGING: Heating for forging must be done slowly and uniformly. Soak through at 1800°-1900°F and reheat as often as necessary, stopping work when the temperature drops below 1600°F. After forging, cool slowly in lime, mica, dry ashes or furnace. O1 tool steel should always be annealed after forging.Heavy sizes should be left to cool in vermiculite or in other insulating media.
  • ANNEALING: Heat slowly to 1400°-1450°F, hold until entire mass is heated through, and cool slowly in the furnace (40F per hour) to about 1000°F, after which cooling rate may be increased. Suitable precautions must be taken to prevent excessive carburization or decarburization.Protect against surface decarburization using controlled atmosphere or by pack-annealing.
  • STRESS RELIEVING: When desirable to relieve the strains of machining, heat slowly to 1050°-1250°F, allow to equalize, and then cool in still air (Strain Relieving).Stress relieve after rough machining.
  • PREHEAT PRIOR TO HARDENING: Warm slightly before charging into the preheat furnace, which should be operating at about 1100°-1200°F.Preheat time in furnace is ¾ Hr. per inch of thickness. Heating up to temperature as slow as possible.
  • HARDENING: After thorough preheating, transfer to the hardening furnace, operating from 1450°-1500°F, depending on the size of the part.Remove all forging or rolling skin prior to hardening. Temper immediately after hardening. Allow to cool to 125-150° F before tempering.
  • QUENCHING: Quench in warm oil and allow to cool in the oil until a temperature of 125°-150°F has been reached, or to where the part can be held in the bare hand, and temper immediately.
  • TEMPERING: O1 tool steel is generally tempered in the range of 300°-600°F. Complete equalization of temperature throughout the tools is essential for good results. Recommended temperature is 350-500° F.

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7 Mill′s test certificate:

EN 10204/3.1 with all relevant data reg. chem. composition, mech. properties and results of testing.

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