The formation of hard spots (e.g. cementite) in cast iron produced in metal moulds is avoided by using a compsn. of 2.80-3.80% C, is not 0.90% Si, is not 0.90% Mn, 0.01-1.0% S, 2.50-4.00% Al and 0.10-1.00% P. The iron has excellent castability and the metal moulds may be water-cooled immediately after casting. Machining is possible even with the addn. of 4% each Cu and Ni, is not 0.25% Cr, is not 0.3% Mo, and is not 0.20% V. Depending on the pre-heating of the mould and the cooling rate, the structure may vary from ferrite/pearlite to pearlite/bainite/austenite, with flake graphite uniformly distributed or in inter dendritic form. The tensile strength and hardness, depending on compsn. and section thickness, are 25-50 kg/mm2, and 180-360 kg/mm2 HB respectively.
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机译：使用compsn可以避免在金属模具中生产的铸铁中形成硬点（例如渗碳体）。 C为2.80-3.80％C，不大于0.90％Si，不大于0.90％Mn，0.01-1.0％S，2.50-4.00％Al和0.10-1.00％P.铁具有出色的可铸性，金属模具可能铸造后立即进行水冷。即使使用addn，也可以加工。分别为4％的Cu和Ni，不大于0.25％的Cr，不大于0.3％的Mo和不大于0.20％的V.根据模具的预热和冷却速率，结构可能与铁素体不同/珠光体到珠光体/贝氏体/奥氏体，片状石墨均匀分布或呈树枝状。抗拉强度和硬度，取决于组成。截面厚度分别为25-50 kg / mm2和180-360 kg / mm2 HB。
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