锰含量对铸态球墨铸铁组织及性能的影响

Effects of Manganese Level on Microstructureand Properties of As-cast Ductile Irno

通过强化孕育处理,细化石墨球,增加共晶团数目,以减轻锰在铸态组织中共晶团晶界处的偏析程度,可将锰量提高至超出常规的限度.如锰高达1.16%时,铸态可得到45~70%铁素体,使δ>10%.试验表明,可将锰视为强化合金元素,得到铸态混合型基体组织,从而显著提高球铁的强度.

The reinforcement inoculation treatment can refine the graphite nodule, increasing the eutectic nodule number and reducing the segregation of manganese element at grain boundary of eutectic nodule in as-cast structure, thus the manganese content exceeds the normal level. At Mn levels up to 1.6%,the ferrite proportion of 45~70% in as-cast microstructure and δ>10% can be obtained.The result of experiment indicats that as-cast mixed matrix is achieved and thus, increasing the strength of ductile iron significantly.