铸态球铁QT450-10的质量控制

Quality Control of As-cast Dutile Iron QT450-10

选自优质原料，依据高碳低硅配料原则，控制原铁液碳硅当量4．4％～4．7％，碳3．6％～3．9％，硅1．3％～1.5％，Mn0．2％～0．3％，S≤0．03％，P≤0．05％，铬硅2．3％～2．6％；选用低稀土FeSiMg6RE2球化剂，严格控制Mg残，RE残，保证Mg残／RE残〉2；采用3次孕育法，控制出铁温度在1500-1520℃，浇注温度在1420～1450℃。成功、稳定、大批量地生产了铸态QT450-10各种出口至欧洲、北美等地的电力线路金具、索具及工程机械球铁件。生产中去除了退货工序，提高了生产效益，取得了良好的技术经济效果。

The mass production of as cast ductile iron castings of grade QT450-10 was successfully achieved with stable result by selecting high grade raw materials and controlling chemical in high carbon and low silicon as the 0E=4.4%-4.7%, C 3.6%-3.9%, Si 1.3%-,1.5%, Mn 0.2%- 0.3%, S≤0.03%, P≤0.05%, Cr-Si addition 2.3%-2.6%. Some Technical methods were also taken as selecting low Real Earth containing spheroidal agent FeSiMg6RE2, strictly controlling residual Mg and RE content to Mg （ residual ） /RE （residual）〉2, and post inoculations as well as controlling liquid iron tapping temp. 1 500- 1 520℃ and pouring temp. 1 420-1 450℃. Ductile iron castings of electric power line metal hardware and parts for construction machinery made by this way were export to Europe and North American with no rejected rate which brought fine profit and good economic effect to the company.