Physical Properties. Forging and Annealing D2 is generally forged at a low temperature and is not allowed to exceed ˚F (˚C). These steels are designated as group D steels and consist of D2, D3, D4, D5, ,  · specification AISI D2, W.-NrDelivery condition Soft annealed to approxHB Color code Yellow/white General Forming HRC Tools for: Bending, Steel D2 is a Tool Steel (High-alloy steel) that has on top of the % of carbon an additional% of manganese, chromium, nickel, and molybdenum. Hardness in