DIN 1.2842 / AISI O2 Tool Steel is used for making tools (punches) and dies for blanking, punching and similar operations; threading and wood working tools, machine knives for the pulp, paper and metal working industries; measuring tools and plastic mould dies.
Round: dia.10-500 mm
Flat: 6-120 x 40-1200 mm
Block: 80-400 x 100-1200 mm
EAF+(ESR) or EAF+LF+VD+(ESR), Hot rolled or Forged, Spheroidizing Annealed, Black surface or Machined surface, UT SEP1921 Class3 D/d
| DIN / W.Nr | JIS | GB | |
| O2 | 1.2842 | ---- | 9Mn2V+Cr |
| Steel Grade | C | Si | Mn | P | S | Cr | Mo | V |
| 1.2842 | 0.85-0.95 | 0.10-0.40 | 1.80-2.20 | ≤ 0.030 | ≤ 0.030 | 0.20-0.50 | ---- | 0.05-0.15 |
| O2 | 0.85-0.95 | ≤ 0.50 | 1.40-1.80 | ≤ 0.030 | ≤ 0.030 | ≤ 0.50 | ≤ 0.30 | ≤ 0.30 |
| 9Mn2V | 0.85-0.95 | ≤ 0.40 | 1.70-2.00 | ≤ 0.030 | ≤ 0.030 | ---- | ---- | 0.10-0.25 |
1. Cold work tool steel with high dimensional stability at heat treatment.
2. Very high cracking resistance. High machinability, medium thoughness and wear resistance.
Annealing
680 to 720°C
Slow controlled cooling in furnace at a rate of 10 to 20°C/hr down to approx. 600°C, further cooling in air. Hardness af ter annealing: Max. 220 HB.
Hardening
790 to 820°C
Oil, salt bath (200 to 250°C) up to 20 mm thickness. Holding time after temperature equalization: 15 to 30 minutes. Obtainable hardness: 63 - 65 HRC
Stress relieving
Approx. 650°C
Slow cooling in furnace; intended to relieve stresses set up by extensive machining, or in complex shapes. After through heating, hold in neutral atmosphere for 1-2 hours.
Tempering
Slow heating to tempering temperature immediately after hardening/time in furnace 1 hour for each 20 mm of work piece thickness, but at least 2 hours/cooling in air.For certain cases we recommend to reduce tempering temperature and increase holdingtime.