The production status and trend of the world's iron castings is that the proportion of gray iron castings has dropped significantly, but it still occupies a major position. The output of ductile iron castings has continued to grow, and vermicular graphite iron and special iron have also developed by leaps and bounds. The output of gray cast iron is decreasing year by year, but the proportion of cast iron in cast iron is increasing. Strengthening the experimental research of gray cast iron is undoubtedly the development direction of gray cast iron in my country.


my country's total output of malleable iron ranks in the forefront of the world, but the demand will also increase. Therefore, my country's malleable bent plate cast iron will have great development in the future.


At present, the main gaps in the production of malleable iron in my country are: malleable iron with few varieties and black heart; poor quality; backward galvanizing process; lack of ideal annealing furnace with low energy consumption, good heat preservation and less pollution. The proportion of ductile iron in cast iron castings is still increasing despite the reduction in cast iron production. In the developed West, ductile iron castings are usually used to replace some gray iron castings and malleable iron castings. The output of ductile iron castings in my country is relatively low, and the proportion of cast iron castings is much smaller than that of developed countries. In addition, my country's ductile iron castings also have a large gap in quality and production stability.


The more prominent problems in the production of ductile iron in my country are the strength and toughness of the material, and there are many defects. In addition to factors such as charge, spheroidizing treatment method, and spheroidizing agent, the main reason is that the sulfur content of molten iron before spheroidizing treatment is too loose. Therefore, in order to greatly increase the output of ductile iron in my country, vigorously implement supporting technologies for ductile iron castings that can provide a stable supply.