DIN 1.2842 O2 Tool Steel Oil Hardening Cold Work Steel
1.2842 o2 tool steel
1 1.2842 Introduction:
1.2842 Cold work tool steels belong to the family of high carbon steels that are further classified into oil-hardening steels, high-carbon, high-chromium steels, and air-hardening steels. Oil-hardening cold-work steels are also known as group O steels consisting of O1, O2, O6, and O7 types.
2 1.2842 Applications:
Typical applications for DIN 1.2842 tool steel include medium run dies, press tools, drawing punches, broaches, bushings, lathe centres, chuck jaws, master cavity sinking hobs, plug gauges, thread gauges, thread cutting tools and precision measuring tools. It is also a popular tool steel for cams, cloth cutting knives, cold taps, reamers, collets, cutting hobs, strip slitting cutters, trimmer dies, tube expander rolls, plastic moulds and woodworking knives.
3 Quality Standard:
ASTM A681 – 08 Standard Specification for Tool Steels Alloy.
4 All Grades Comparison:
| ASTM | Material No. | AFNOR | UNI | B.S. |
|---|---|---|---|---|
| O2 | DIN1.2842 | 90 MV 8 | 88 Mn V 8 KU | Bo 2 |
5 1.2842 Chemical Composition(%)
| C | Si | Mn | P | S | Cr | Cr | V |
|---|---|---|---|---|---|---|---|
| 0.85-0.95 | 0.50 max | 1.40-1.80 | 0.030 max | 0.030 max | 0.50 max | 0.30 max | 0.30 max |
6 HEAT TREATMENT:
- FORGING: Heat uniformly to 1000°C. Forge within a range of 850-1050°C reheating if necessary. Cool slowly (preferably in a furnace) to avoid setting up stresses
- ANNEALING:O2 tool steel is supplied in the annealed and machineable condition. Re-annealing will only be necessary if the steel has been forged or hardened. To anneal, heat uniformly to 720°C, equalise, then furnace cool (hardness about 229 Brinell). Fully machined tools in grade O2 tool steel should be packed during annealing.
- HARDENING:Heat uniformly to 790-820°C until heated through. (If possible pre-heat at 300-500°C). Allow thirty minutes per 25 millimetre of ruling section and quench immediately in oil.
- MARTEMPERTINGMartempering of O2 tool steel is an alternative hardening procedure which may be used when suitable salt bath equipment is available.
- TEMPERING: Heat the O2 tool steel uniformly and thoroughly at the selected tempering temperatures and hold for at least one hour per inch of total thickness.
7 Mill′s test certificate:
EN 10204/3.1 with all relevant data reg. chem. composition, mech. properties and results of testing.
