D2 COLD WORK TOOL STEEL
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STRESS
RELIEVING |
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| Heat to 650°C / 700°C. Hold for 2-4 hours and furnace cool. |
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HARDENING |
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| Before heat
treatment, sufficient machining should be carried out to remove surface decarburisation. Preheat thoroughly at 800°C / 850°C and then raise more rapidly to 1010°C / 1030°C in a controlled atmosphere or, preferably, a neutral salt bath. A useful alternative is box hardening using spent charcoal places away from the working surfaces. The high chromium content of this steel makes reactions sluggish, therefore adequate soaking times must be allowed. Cool in air. D2 may be oil quenched from 970°C / 990°C to give a marked improvement in toughness. |