The precipitation mechanism of AIN in high magnetic induction oriented silicon steel during the soaking process is systematically analyzed by the method of combining thermodynamics and kinetic calculations. The calculation results show that

at the soaking temperature of high magnetic induction oriented silicon steel

AIN in the  α+γ two-phase and has the thennodynamic precipitation conditions. With uniform nucleation

grain boundary nucleation and dislocation nucleation three kinds of mechanisms

the critical nucleation size of AIN is in the same order of magnitude and decreases with decreasing temperature. At the same temperature

the critical nucleation work of AIN grain boundary nucleation is the smallest and the relative nucleation rate is the largest

that is

grain boundary nucleation is easier to occur. The fastest precipitation temperatures for uniform nucleation

grain boundary nucleation and dislocation nucleation of AIN in a phase and 7 phase are 1203 K

1303 K

1243 K and 1213 K

1305 K

1233 K

respectively. AIN mainly nucleates at grain boundaries at soaking temperature.