Research On Annealing Process Of Non-oriented Electrical Steel For Rare Earth New Energy

The new energy automobile have three superiority:simple?environmental protection?economical,are the future development inevitable trend.Drive motors is one of the three core components of new energy vehicle,miniaturization?high-performation?high-effciency are the future direction development.High-strength non-oriented electrical steel sheet is the key materials for driving motor rotors,High-speed motors capable of tens of thousands or even one hundred thousand revolutions per minute are being used.At the same time,the conventional rotor core can not bear the centrifugal force produced by high-speed rotation,which puts forward higher requirement for the strength of non-oriented electrical steel.Based on strict requirement of the new energy drive motor,non-oriented electrical steel have better mechanical properties,such as high magnetic induction?low iron loss and high strength.Based on non-oriented electrical steel with 2%Si content,adding Nb,Ti and trace rare earth Ce,the secondary cold rolling thickness of 0.32 mm was put into the tubular high temperature protective atmosphere furnace for 800?830?860?890?920?950?×5 min with annealing temperature.The recrystallized microstructure was observed by metallographic microscope and microstructure evolution was studied with annealing temperature;The texture was measured by X Ray diffractometer and influence of annealing temperatures on texture was studied;Zeiss Sigma 300 was used to analysis micro-texture;The morphology and size of precipitates were observed by analytical transmission electron microscope;Using TD8510 silicon steel sheet measuring instrument,GNT50 electronic universal testing machine,to test and analysis magnetic and mechanical properties with annealing temperatures.The result shows recrystallized grains can be seen in the surface and central at 800⁹20?annealing,higher annealing temperature,more fully recrystallized.After annealing at 950?,complete recrystallization occurred and average grain size was 48.29 um.After annealing at 800?,?texture strength was stronger,?texture is weakened and a little cube texture.At 830?annealing and higher temperature,?texture strength was obviously weakened cube texture basically disappeared and?texture strength was significantly enhanced.A large amount of?Nb,Ti?C particles were precipitated during annealing of high strength non-oriented electrical steel containing Nb and Ti.As annealing temperature increased,size of?Nb,Ti?C increased and distribution density decreased.The size of rare earth inclusions were large,?Nb,Ti?C nucleated and growed up around rare earth inclusions as the core.The tensile strength and yield strength increased first and then decreased with the increasing temperature,elongation increased,magnetic induction B₅₀0 increased first and then decreased,iron loss P_1.5/50?P_1.0/400.0/400 decreased gradually.After 860?×5 min,strength and magnetic properties of the product match best.