OHNS

Grade Introduction:

OHNS steel is a general-purpose tool steel that is typically used in applications where alloy steels cannot provide sufficient hardness, strength, and wear resistance. Chemical composition of OHNS is Carbon 0.94%, Manganese 1.2%, Silicon 0.30%, Chromium 0.50% and Vanadium 0.15%.

Grade Application:

• Blanking and stamping dies,
• Punches,
• Rotary shear blades,
• Thread cutting tools,
• Milling cutters,
• Reamers,
• Measuring tools,
• Gauging tools,
• Woodworking tools,
• Broaches,
• Chasers.

Equivalent grades:

STANDARDS 100MnCrW4 O1 DIN 2510 AISI O1 AFNOR 90MWCV5 JIS SKS3

Chemical composition:

The following table shows the chemical composition of OHNS steel:

Element C Si Mn P S Cr W
Content (%) 0.85-1.00 0.15-0.35 1.00-1.20 0.03 Max 0.03 Max 0.50-0.70 0.50-0.70

Hardness:

Max. 230

Heat treatment:

Soft Annealing °C 750-780
Cooling Furnace
Hardness HB Max. 230
Stress-relief Annealing °C Approx. 650
Hardening °C 780-820
Quenching Air, Oil, Salt Bath 180-220 °C
Hardness after quenching HRC 65

Hardening:

O1 steels should be heated uniformly to 780-820°C (1436-1508°F) until completely heated through. If needed, the steels can be preheated at 300-500°C (572-932°F). About 30 min/per 25 mm of the ruling section is to be provided and then the steels should be immediately quenched in oil.