The general chemical compositions of microalloyed intragranular ferrite steels are 0.2~0.4C

0.2～0.8Si

1.0~1.7Mn

0.05～0. 15V. It is a main measure to increase the strength and toughness of ferite-pearlite microalloyed steel using recrystallized forging and rolling to control cooling rate in phase transformation range in order to promote formation of fine dispersed intragranular ferrite structure. Recently an important advance to increase strength and toughness of this steel is to select suitable deoxidizing process

get fine

dispersed oxides with definite ingredient which become precipitated nucle- us of MnS

VN and V4C₃ .The chemical compositions and production of microalloyed intragranular ferrite steels at home and abroad are presented and the formation mechanism of intragranular ferrite is analyred in this paper.