铸态QT600-10的生产工艺

介绍了汽车铸件的结构以及技术要求,根据技术要求将球化处理后的化学成分控制在:w(C)3.6%~3.8%,w(Si)2.6%~2.9%,w(Mn)0.25%~0.45,w(P)≤0.030%,w(S)≤0.015%,w(Mg残)0.03%~0.04%,w(RE残)0.01%~0.02%,采用5 t中频炉熔炼,原铁液出炉温度控制在1 480~1 520℃,采用冲入法进行球化处理,选用低RE的FeSiMg6RE2球化剂,粒度为10~25mm,加入量为每包铁液量的1.1%;采用粒度为3~8 mm的CaBa复合孕育剂进行一次孕育,浇注时使用粒度为0.3~1 mm的高CaBa复合孕育剂进行二次随流孕育。最终生产铸件的球化等级控制在2~3级,石墨球大小6级,抗拉强度不低于600MPa,伸长率不低于10%,且珠光体体积分数及力学性能波动均在10%以内。

Production of As-Cast QT600-10 Grade Nodular Iron

The configurations and technical requirements of automotive castings were introduced. Based on the technical requirements,the nodularizing treated composition was controlled in the range of w（C） 3.6%-3.8%,w（Si） 2.6%-2.9%,w（Mn） 0.25%- 0.45%,w（P）≤0.030%,w（S）≤0.015%,w（Mg 残） 0.03%--0.04%,w（RE 残） 0.01%-0.02%;5 t medium frequency induction furnace was adopted for melting; the composition of the base iron was controlled in the range of 1 480-1 520 ℃ ; pour-over process was used to conduct nodularizing treatment;a low RE-content nodularizing alloy FeSiMg6RE2 with grain size of 10-25 mm was used and its adding amount was of 1.1% per ladle iron melt;the CaBa-coutaining composite inoculant with grain size of 0.3-1 mm was used for first inoculation treatment（ladle inoculation）;and the high CaBa-containing inoculant was used for secondary inoculation （pouring stream inoculation）. The nodularizing grade of the finally produced castings was controlled in 2-3 class,their tensile strength was not lower than 600 MPa;elongation was not lower than 10% and the fluctuation of pearlite volume fraction and mechanical properties was controlled in the range of 10%.