【作者】 王浩；

【导师】 李长生；

【作者基本信息】 东北大学 ， 材料加工工程， 2015， 博士

【摘要】 取向硅钢是一种重要的软磁材料,具有优良的磁学性能,是制造变压器、磁屏蔽材料等不可或缺的原料,广泛应用于电力、电子等相关行业。取向硅钢的磁学性能一直备受专家学者的关注。球刻痕是欧洲硅钢公司开发的一种刻痕方法,作为机械刻痕法的一种,既克服了破坏绝缘层的缺点,又可以达到理想的刻痕效果,球刻痕对取向硅钢磁学性能的研究直接决定其应用的广泛性。本文研究了球刻痕对Fe-3%Si取向硅钢磁性能的影响,建立了取向硅钢磁畴、刻痕间距与铁损等参数间关系的修正模型,分析了球刻痕对取向硅钢磁导率、矫顽力及磁屏蔽效能的影响规律,研究了刻痕法及涂层、应力对巴克豪森噪声等磁性能的影响。论文的主要工作及研究成果如下：(1)采用标准的Epstein试样沿不同方向进行磁化,获取磁化参数并对其进行研究,基于传统的椭圆模型提出了抛物线拟合和综合模型,并分别对BC1普通取向硅钢、BH1高磁感取向硅钢在不同磁化方向上的磁导率进行分段拟合,BC1、BH1取向硅钢的分段拟合模型与实验测量值吻合良好。(2)将磁场强度与磁感应强度分别按傅里叶级数展开,构建了Fe-3%Si取向硅钢的磁滞回线模型,提出了采用固定角度法和最小二乘法确定兔度、磁感应强度和磁场强度等待定参数的方法,该模型拟合效果良好。(3)研究了球刻痕对Fe-3%Si取向硅钢铁损的影响。从磁畴能量等角度分析降低铁损的原因,推导了磁畴、刻痕间距等与取向硅钢铁损间的关系模型,得到了最佳刻痕间距的计算方法。将取向硅钢的铁损按磁滞损耗、涡流损耗、反常损耗进行分离,并计算所占比例及球刻痕对各部分铁损的影响。(4)研究了球刻痕对Fe-3%Si取向硅钢磁导率的影响。从填充磁力线角度分析磁导率随磁感应强度变化的规律。对屏蔽效能的反射损耗、吸收损耗、内部多重损耗进行了分析。球刻痕可大幅提高取向硅钢的磁导率和磁屏蔽效能,同时会取得降低取向硅钢矫顽力的效果。经过球刻痕处理后,CC1普通取向硅钢的趋肤深度明显降低,CH1高磁感取向硅钢的趋肤深度在磁感应强度大于0.2 T时才逐渐下降。(5)研究了球刻痕对Fe-3%Si取向硅钢巴克豪森噪声的影响,刻痕后CC1普通取向硅钢的巴克豪森噪声值上升,而CH1高磁感取向硅钢的巴克豪森噪声值下降。拟合了铁损和巴克豪森噪声两者问的线性关系,线性拟合度高。根据巴克豪森噪声与铁损值之间的关系,提出了一种取向硅钢铁损值的无损检测方法,该方法测试精度高、线性拟合度良好、容易实现。研究了表面涂层和拉应力对取向硅钢巴克豪森噪声的影响。去除表面涂层导致CC1与CH1取向硅钢的巴克豪森噪声值上升。计算了磁畴壁的移动速度,验证了铁损与巴克豪森噪声的关系。更多还原

【Abstract】 Grain-oriented silicon steel is a significant soft magnetic material with excellent magnetic properties, which is also an essential raw material to manufacture transformers and magnetic shielding apparatus, and it is widely applied in electrical, electronics and other related industries. The magnetic properties of grain-oriented silicon steel have attracted attention of experts and scholars. Ball scribing method is a method developed by the European Silicon Steel Corporation, which not only overcomes the shortcomings of the destruction of the insulating layer as a kind of mechanical scribing, but also achieving the desired scribing effect. The effect of ball scribing on magnetic properties of grain-oriented silicon steel directly determines its wide applications. Effect of ball scribing on magnetic properties of Fe-3%Si grain-oriented silicon steel was studied in this thesis, and revised relation models among parameters of magnetic domain, scribing width and iron loss were built. Effect of ball scribing on permeability, coercive force and magnetic shielding was analyzed, and effect of ball scribing, insulation layer and stress on Barkhausen noise was also studied. The main work and research results of this thesis are as follows:(1) Standard Epstein grain-oriented silicon steel samples were magnetized along different directions, and magnetization parameters were obtained and studied. The parabolic and hybrid models were built based on the traditional oval model, and permeability of conventional grain-oriented silicon steel BCl and high penneability grain-oriented silicon steel BH1 were simulated with sectional fitting respectively, and the simulation results of BCl and BH1 grain-oriented silicon steel coincide well with measured results.(2) The magnetic field strength and the magnetic flux density were expanded respectively according to the Fourier series, and the magnetic hysteresis loop model of Fe-3% Si grain-oriented silicon steel was built. The fixed angle method and the least squares method were applied to calculate the undetermined parameters, which achieves high fitting degree.(3) Effect of ball scribing on iron loss of Fe-3%Si grain-oriented silicon steel was researched. Iron loss reduction was illustrated from the respective of the magnetic domain energy. Relationship among iron loss and parameters such as domain width and scribing width was rederived and optimum scribing width was verified, and the calculation method of poptimum scribing width was obtained. Iron loss of grain-oriented silicon steel was separated into three parts, hysteresis loss, eddy current loss and abnormal loss, and their proportions were calculated, the effect of ball scribing on them were also analyzed.(4) Effect of ball scribing on magnetic permeability of Fe-3%Si grain-oriented silicon steel was studied, and variation of magnetic permeability with magnetic induction was analyzed from the perspective of filling of magnetic field lines. Magnetic shielding efficiency of silicon steel was analyzed, the reflection loss, absorption loss, internal multi-reflection loss were illustrated respectively. Ball scribing can significantly increase the permeability and the magnetic shielding efficiency of grain-oriented silicon steel. Meanwhile, ball scribing could decrease coercive force of the silicon steel. The skin depth of silicon steel descended apparently after ball scribing, and skin depth of conventional grain-oriented silicon steel CC1 dropped obviously, and that of high permeability grain-oriented silicon steel CHI gradually descended while the flux density is above 0.2 T.(5) Effect of ball scribing on Barkhausen noise of Fe-3%Si grain-oriented silicon steel was researched. After ball scribing Barkhausen noise of conventional grain-oriented silicon steel CC1 increased significantly, while Barkhausen noise value of high permeability silicon steel CHI declined sharply. A linear relationship between Barkhausen noise and iron loss was fitted, and the fitting degree is high. According to the relationship between Barkhausen noise and iron loss value, a non-destructive testing method was proposed. The non-destructive testing method possesses advantages of high precision, good linear fitting degree and being easy to implement. Effect of surface coating and tensile stress on Barkhausen noise was also studied, and coating removal leads to increase of Barkhausen noise of CC1 and CHI grain-oriented silicon steel. Domain wall movement velocity was calculated, and relevance of iron loss and Barkhausen noise was confirmed.更多还原