The use of cast iron has a long history; according to research, China began using cast iron as early as the Western Han Dynasty (approximately 2000 years ago).
Ductile iron, as a high-strength cast iron material, was developed in the 1950s, and its comprehensive properties are close to those of steel.
The international metallurgical industry previously believed that ductile iron was invented by the British in 1947. However, in 1981, Chinese ductile iron experts, using modern scientific methods to study ancient Han and Wei dynasty iron artifacts, determined that spheroidal graphite cast iron already existed in China during the Han Dynasty.
China's ductile iron production started very early; it was successfully developed and put into production in 1950. China's annual ductile iron production once reached 2.3 million tons, ranking third in the world after the United States and Japan. The successful development of rare earth magnesium spheroidizing agents suitable for China's national conditions has promoted the development of production technologies in areas such as as-cast ductile iron and austenitic-bainitic ductile iron.
