球铁卡块铸件质量控制的工艺研究

Research on Controlling the Quality of Ductile Iron Segment Casting

针对球铁卡块铸件伸长率低的情况,在分析其结构和凝固过程特点的基础上,结合实际生产条件,采用均衡凝固理论设计浇冒口,通过强化补缩消除了缩松缺陷,使微观组织致密;采用瞬时孕育工艺等措施,使石墨明显细化,铁素体含量提高,铸件本体的力学性能明显得到改善,达到了QT450-10的要求,伸长率甚至达到15%。

In order to improve the elongation of ductile iron segment casting, the structure and solidification process of the casting were analyzed. Combined with the practical conditions, the pouring system and riser were designed according to the proportional solidification theory. The shrinkage porosity are eliminated and the microstructure of the casting is more denser by strengthening the feeding;The graphite is refined obviously, the fraction of ferrite is increased and the mechanical properties are improved significantly through inoculation, the strength can reach the specification of QT450-10, the elongation reaches up to 15%.