含Bi孕育剂在奥贝球墨可锻铸铁中的作用研究

Study on Role of inoculant with Bi in Austenitic-Bainitic S.G. Malleable Cast Iron

研究了Bi及含Bi孕育剂对奥贝球墨可锻铸铁组织和性能的影响。结果表明,采用微量的Bi、Bi加FeSi或Bi加CaSi对奥贝球墨可锻铸铁进行孕育处理,在保证铸态为白口的前提下,能形成大量细小均匀的石墨球,从而降低退火温度,缩短退火时间,提高奥贝球墨可锻铸铁的力学性能。其中Bi加CaSi复合孕育处理效果最佳。

The effects of Bi and inoculant with Bi on microstructures and mechanical properties of austenitic -bainitic spheroidal graphite malleable iron (AMI) have been stu'died.The results have shown that inoculation processing by adding Bi,Bi plus FeSi or Bi plus CaSi compound inoculant can form lots of small spheroidal graphites in as cast white matrix structures,reducing the anneal temperature and time for the first stage graphitization while increasing the mechanical properties of AMI. Best effect can be obtained when Bi plus CaSi compound inoculant used.