Through rationally selecting chemical composition and applying appropriate nodualarization agent and inoculation agentas-cast pearlite ductile iron of grade QT550-6 has been produced stably.

• 通过合理选择化学成分和选用合适的球化剂与孕育剂,稳定地生产出牌号为QT550-6的铸态珠光体球墨铸铁件。