前言球墨铸铁作为一种新型结构材料,自一九四八年问世以来,在世界各国得到了迅速的发展和广泛的应用。但是,随着大截面球铁件应用的不断增加,发现在缓慢冷却条件下,断面中心石墨畸变—即出现球化衰退现象。产生了大量的蠕虫状石墨这给大截面球铁 Foreword As a new type of structural material, ductile iron has been rapidly developed and widely used in all countries in the world since its publication in 1948. However, with the increasing application of large-area ductile iron parts, it is found that the graphite in the center of the cross-section distorts under the condition of slow cooling, that is, the phenomenon of spheroidization degeneration occurs. Produced a lot of worm-like graphite which gives large cross-section ductile iron