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一、概述1.冲天炉纯铬铸铁的缺点当灰铸铁中加入络时,能提高踌铁的强度、硬度、激冷深度,并增进其耐热性与耐蚀性。由于铬能形成极稳定的碳化物,在高温暴露下不会分解,故能阻止或延迟铸铁在高温下的生长,而且在酸蚀中亦能保持其强度。铬量越多,则其耐热耐蚀性能亦越佳。例如含铬15%和碳3.5%的冲天炉铸铁在850～900℃的高温氧化性气氛中,能显示出卓越的抗热性。不过,这种铸铁是很硬且脆的。在寻常灰铸铁中,含铸量在3%或以上时,断面就呈白口组织,只有当含碳量降低到1.35～2.0%范围内时,才可随着含碳量
First, an overview of the shortcomings of pure cupola cast iron cup when the cast iron is added to the network, he can improve iron strength, hardness, chilling depth, and enhance its heat resistance and corrosion resistance. Because chromium forms extremely stable carbides and does not decompose at high temperatures, it prevents or delays the growth of cast iron at elevated temperatures and maintains its strength during acid etching. The greater the amount of chromium, the better its heat and corrosion resistance. For example, cupola cast iron with 15% chromium and 3.5% carbon can exhibit excellent heat resistance in a high-temperature oxidizing atmosphere of 850 to 900 ° C. However, this cast iron is very hard and brittle. In ordinary gray cast iron, when the cast amount is 3% or more, the cross section is whitened, and only when the carbon content is reduced to within the range of 1.35 to 2.0%, the carbon content