Effect Of High Temperature Annealing On Secondary Recrystallization Behavior Of Low Temperature Oriented Silicon Steel

In this thesis,the effects of two different decarburization annealing processes on the primary and secondary recrystallization microstructure and texture were studied by OM,SEM,EBSD,EDS and other analytical techniques using bismuth low temperature oriented silicon steel slabs as experimental materials.The effects of three different high temperature annealing atmospheres on the microstructure,texture and magnetic properties of secondary recrystallization were studied.The evolution of microstructure,texture and inhibitor of low temperature oriented silicon steel with different holding time at high temperature annealing was studied.The main conclusions are as follows:1)After cold-rolled sheet is 850°C,the microstructure is more fine and uniform after annealing for 5 min,and the favorable texture is more than{111}<112>,but the texture content is lower;the high temperature annealing is 850°C.The Goss texture content of the annealed sample at 5 min is higher at 95.8%,the off angle is smaller,and the magnetic properties are better,B₈₀₀=1.89T,P_1.7/50=1.33W/kg.2)After high temperature annealing in 25%N₂+75%H₂ atmosphere,the sample undergoes complete secondary recrystallization and the grain size is relatively uniform;and its texture is mainly based on sharp Goss texture,and the content reaches 93.1%,better magnetic performance.3)When the high temperature annealing at 1050°C is maintained from 0h to 2h,the grain size increases slightly,but the microstructure is relatively uniform;mainly based on{111}<112>and{411}<148>texture;when reaching 5h the partial Goss nucleus grew abnormally;when it reached 25h,complete secondary recrystallization occurred,and the Goss texture content reached 91.1%.The inhibitors in the sample mainly include Nb（C,N）,Mn S,Cu_xS and Al N;the size of the inhibitor gradually increases with the prolongation of the holding time,and the coarse second phase particles are completely formed at 25h,and the grain boundary nails are lost.Figure 50;Table 11;Reference 54...