中磷白口铸铁组织和性能的研究

Study on the Structure and Properties of Medium phosphorus White Cast Iron

随着白口铸铁含磷量的增加，其结晶组织由共生共晶变为离异共晶，渗碳体独立生长为断续分布的网块状或板条状，共晶奥氏体依附在初生奥氏体枝晶上生长。三元磷共晶分布于渗碳体断网及板条搭接处。中磷白口铸铁的宏观硬度和显微硬度高于普通白口铸铁，但冲击韧性略有降低。

The structure and mechanical properties of medium phosphorus white cast iron have been stu died,the results revealed that,as the phosphorus content in the white cast iron increases,its structure is changed from coupled eutectic into divorced eutectic,the cementite independently grows and forms net chunk with interrupted distribution or plat chunk,and the eutectic austenite grows on the primary austenite dendritic.The ternary phosphide occurs in the breaks of net chunk cementite or the joints of the plate chunk cementite.The hardness and its microhardness of medium phosphorus white cast iron are higher than those of the common white cast iron,but its impact toughness slightly decreases.