铸态铁素体球铁的模拟焊接热影响区组织与力学性能

Microstructures and Mechanical Properties of the Simulated Heat Affected Zone of Arc Welded As Cast Ferritic Ductile Iron

系统地研究了铸态铁素体球铁的模拟焊接热影响区组织与力学性能，揭示了铸态铁素体球铁的高硅低锰特性对组织与力学性能的影响。指出热影响区的高碳马氏体使其塑性与韧性严重下降，预热４００℃可消除马氏体，并使热影响区的力学性能显著改善。

The microstructures and mechanical properties of HAZ of arc welded cold as cast ferritic ductile iron have been investigated. The effect of chemical composition characteristic which is high content of silicon and low content of manganese on the behavior of HAZ of the ductlie iron is revealed. High carbon martensite appearing in HAZ decreases sharply the ductility and toughness. The effect of preheat on microstructures and mechanical properties of HAZ of arc welded as cast ferritic ductile iron are studied. The result illustrates that 400℃ is the optimum preheat temperature. Under this condition, the martensite of HAZ is replaced by pearlite and ferrite. The ductility and toughness of HAZ are greatly improved.