低温球墨铸铁工艺的技术研究

Research on the Technology of Low Temperature Ductile Iron Processes

对低温(-60℃)球墨铸铁材料的化学成分、配料、熔炼、球化、孕育、浇注、热处理工艺进行了分析,并对各工序提出了具体的成分、温度、加入量等控制措施。结果表明,通过合理的化学成分配比和微量Ni元素的加入,控制1 530～1 550℃铁液出炉,900～920℃高温热处理工艺,提高了低温球墨铸铁材料力学性能(低温-60℃时,抗拉强度≥425 MPa、冲击吸收功在12～14 J之间、伸长率≥22%),该性能满足了轨道交通、风电、核电、南北极开发等领域高端装备制造业的需求。

For low temperature （-60 ℃ ） the chemical composition of ductile cast iron materials, ingredients, melting, spheroidization and inoculation, casting, heat treatment process were analyzed, and puts forward the specific composition of each working procedure, such as temperature, content of control measures. The results show that through the reasonable chemical composition and the addition of trace elements of Ni, control of molten iron temperature 1 530 ℃ to 1 550 ℃, high temperature heat treatment process with 900-920 ℃, the mechanical properties of low temperature ductile iron materials mechanics is improved, such as low temperature -60 ℃, the tensile strength≥425 MPa, the impact energy is 12-14 J, elongation is ≥22%. The mechanical properties meet the demand of high-end equipment manufacturing industry in the fields of rail transit, wind power, nuclear power and polar development.