硅固溶强化铁素体基球墨铸铁性能研究进展

Research development in property of Si solution strengthened ferritic ductile iron

介绍了硅固溶强化铁素体基球墨铸铁(或高硅球铁)的发展历程,对比分析了高硅球铁与传统球铁的拉伸性能、冲击性能、断裂韧性、疲劳强度、热导率、热循环体积变化、机械加工性能。分析表明:虽然通过控制残余镁含量、快冷等措施已经可使高硅球铁综合拉伸性能高于标准中的指标,但是常温和高温脆性的机理仍有待进一步研究;高硅球铁在疲劳强度、动态断裂韧性、热循环体积变化、机械加工性能方面要优于传统球铁。基于此,对高硅球铁发展前景进行了展望:1)高硅球铁在常温和高温脆性机理方面的研究是今后的研究重点,脆性机理研究的深入与进步将进一步提升高硅球铁的综合力学性能;2)高硅球铁与传统球铁相比有更高的的屈强比、动态断裂韧性和疲劳强度,未来会更多地应用在有轻量化需求的铸件上;3)综合考虑全生命周期成本,高硅球铁在绿色化发展趋势中更具优势。

The development of Si solution strengthened ferritic ductile iron(or high silicon ductile iron) was reviewed in this paper.The tensile property,impact property,fracture toughness,fatigue strength,thermal conductivity,volume stability under thermal cycle and machining property of both high silicon iron and conventional ductile iron were analyzed.It reveals that the brittleness mechanism at room temperature and high temperature still need further research although better tensile property can be obtained by controlling the residual Mg content and higher cooling rate.The high silicon ductile iron is superior to the conventional ductile iron in terms of fatigue property,dynamic fracture toughness,volume stability under thermal cycle and machining property.Based on this,the development prospect of high silicon ductile iron can be concluded as:1) The study of brittleness mechanism of high silicon ductile iron at room temperature and high temperature will still be the focus of further research,and the deepening and progress of the brittleness mechanism resseaarch will further improve the comprehensive mechanical properties of high silicon ductile iron;2)Compared with traditional ductile iron,high silicon ductile iron has higher flexion ratio,dynamic fracture toughness and fatigue strength,and will be more used in the future for lightweight casting.3) Considering the whole life cycle cost,the high silicon ductile iron has more advantages in the green development trend.