Cu Element Of Non-oriented Electrical Steel Microstructure, Texture And Resistance To Impact Resistance

Non-oriented electrical steel sheet is easily affected by the emulsifier, air humidity and the surface cleanliness during the actual production, resulting in rusting of steel surface, as a result it affects the surface quality of steel plate. The surface quality of electrical steel has a great impact on the magnetic properties and sale value during selling.It is generally believed that the addition of Cu element in non-oriented electrical steel not only can improve the magnetic properties but also can improve corrosion resistance. Japan began trail production of corrosion resistance electrical steel in1973, but its design ideas are around the Cr elements. Although it has great success, still it is difficult to obtain the magnetic properties and excellent corrosion resistance altogether.In this paper, we get eventually precipitates and inclusions by thermodynamic calculation in non-oriented electrical steel and then the study found that the MnS and AlN precipitation temperature is not affected by the Cu content, but the CuS and Cu2S precipitation temperature gradually increased with the increase of Cu content.Research the Cu element impact on the organization and texture of hot rolled non-oriented electrical steel show that due to the influence of surface segregation of Cu element, the surface grain size is significantly smaller than the center layer, while the poor uniformity of grain size in the sample. With the increase of content of Cu, the density of surface texture decreased in hot rolled plate. The strength of favorable texture gradually decreases, however, unfavorable texture component gradually increased; in1/4layer, there are cube texture, rotated cube texture and Goss texture, also produce a great intensity texture of{111}<110> and{111}<112> texture. There are much of stable texture components in center layer, which unfavorable texture components increases but favorable texture components are reduced.Study of grain size impact on the texture in annealing plates show that grain size distribution is not uniform in annealing plates; grain size changes directly affect the texture component. The texture of large grain is{111}<110> and{111}<112> texture and other unfavorable texture, while the main components are cube texture, rotated cube texture and a small amount of{111}<110> and{111}<112> texture in small grain. Favorable texture component increases but unfavorable texture reduces. The main effect is that the Cu and P with different diffusion coefficients, the diffusion of Cu prevented P analytical report, resulting in a large number of Cu, P element segregation to grain boundaries, hinder grain growth, leading to {100}<Ovω> components increase.Study of recrystallization texture of non-oriented electrical steel show that recrystallization temperature increased gradually with the increase of Cu content, and the precipitates of Cu significantly delayed the recovery process, as a result the temperate of recovery process increase significantly. The first nuclear textures are Goss and{112}<112> textures, with the increase of annealing temperature, the{111}<112> component grew gradually annexed the other texture, led {111}<112> to become the main component.Study the effect of Cu on magnetic properties of non-oriented electrical steel show that the magnetic properties does not appear linear increase or decrease with the Cu content. Without normalizing, P15/50gradually decrease and B50increase singificantly. The best magnetic property appearance at1000℃, the best P15/50is4.8W/kg and the best magnetic induction B50is1.76T. After normalization, the magnetic properties gradually increase with the annealing temperature, and the lowest P15/50reached4.3W/kg, the best magnetic induction B50reached1.80T.Research the corrosion resistance of non-oriented electrical steel which content Cu element show that the corrosion resistance of the samples gradually increased with increasing Cu content; after168h etching, specimens of0.1%Cu,0.2%Cu corrosion and0.3%Cu corrosion is deep, shallow. Large spiral corrosion pit corrosion morphology of samples, with the increase of Cu content, the number of the helical pit corrosion morphology of decrease. At high magnification microscope, corrosion morphology of0.1%Cu are mainly spherical radius smaller together, with the increase of Cu content, the radius increases gradually, but by0.3%, the corrosion morphology into flock.