Microstructure And Texture Evolution Of 50W800 Non-oriented Silicon Steel By Batch Annealing

At present,energy shortage is becoming increasingly prominent in the world,and more efficient use of electric energy as the main form has become an important topic.Silicon steel is widely used in the process of electric energy transmission and conversion,reducing the loss in the process of electric energy conversion and improving its performance is the theme of improving the efficiency of electric energy utilization in the past century.In this paper,the recrystal ization annealing of non-oriented silicon steel is carried out by batch annealing process.the evolution of microstructure,texture and precipitates of 50W800 non-oriented silicon steel in the heating and holding stages of batch annealing is studied in detail,and the effect of batch annealing process on the magnetic properties of non-oriented silicon steel is studied,The key parameters of batch annealing process are provided for production unitsThe main experimental schemes are as follows:(1)A series of holding temperatures are set every 25? between 500? and 700?,keep samples at each temperature for 1 hour,then take them out and cool them in water quickly.The recrystal ization temperature was determined by observing the change of metal ographic structure and texture.(2)The samples were heated at a heating rate of 50?/h.At the heating stage between 500? and 750?,the samples were taken out every 25 ? and cooled in water.Then observe the change of microstructure during the heating process.(3)Four heating rates of 50?/h,60?/h,80?/h and 100?/h were set,and the temperature was raised to 745? and kept for 10 h.After heat preservation,take out the samples and cool them in air.The magnetic properties,metal ographic structure,macro texture and precipitates were detected after annealing,in order to explore the effect of heating rate of batch annealing on non-oriented silicon steel.(4)The temperature was raised to 400? at a heating rate of 100?/h and then to 740? at a heating rate of 60 ? /h.After holding for 4h,6h,8h and 10 h respectively,samples are rapidly cooled in air.The magnetic properties,metal ographic structure,macro texture and precipitates were detected after annealing,in order to explore the evolution of microstructure and texture of non oriented silicon steel during soaking time extension of batch annealing.The main conclusions are as fol ows:(1)The recrystal ization temperature of 50W800non-oriented silicon steel is about 600 ?.(2)With the increase of heating temperature,the{100} texture proportion of 50W800 non-oriented silicon steel decreases gradually,and the{110} and {111} texture proportion increases gradually.After complete recrystal ization,the{001}<110> texture and the {112}<110> texture strength decreased sharply,the {111}<110>texture decreased gradually,and the {111}<112> texture increased gradually.(3)With the increase of heating rate,the grain size of 50W800 non-oriented silicon steel increases gradually,{001}<110> and {110}<001> texture intensities increase,while {110}<110> and{111}<110> texture intensities decrease;The size of precipitates gradually increases and the area density gradually decreases.When the heating rate reaches 100?/ h,the microstructure and texture deteriorate and the magnetic properties decrease.(1)With the prolongation of holding time,the grain size of 50W800 non-oriented silicon steel increases gradually,and{001}<110>,{110}<110>,{110}<001> texture strength decreased,while {100}<001>,{111}<110>,{111}<112> texture strength increased;AlN and MnS precipitates coarsened gradually,and the area density decreased gradually.The results show that the magnetic property is ideal when holding for 8h.