Wang Yuqi, Gao Zhenyu, Luo Li, Chen Chunmei, Zhao Zhiyang, Song Renbo, Zhang Yingchao
Angang Steel Co., Ltd., Anshan 114021, China.
School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China.
Materials (Basel). 2023 Jul 28;16(15):5311. doi: 10.3390/ma16155311.
The magnetic domains of non-oriented electrical steel bearing cumulative thermal compressions made by a Gleeble 3500 Thermal System were observed using an atomic force microscope (AFM). The component forces, comprising the magnetic forces between the AFM probe and magnetic domains of the samples, along the freedom direction of the probe, were measured, and they formed the value fluctuation of the magnetic domains. The fluctuations of the magnetic domains were analyzed by examining the power spectral density (PSD) curves. The hysteresis curves of the samples were measured using a highly sensitive magnetic measurement system. An analysis of the magnetic force microscope (MFM) maps suggested that some magnetic domains were compressed into crushed and fragmented shapes, similar to the microstructure of deformed grains. Meanwhile, some were reconstructed within the thermal compressions, like dynamic recrystallization microstructures. Meaningfully, the MFM probe moved and deformed the proximal magnetic domains of tested samples within the region of its weak magnetic field. The peak positions of the magnetic domains with a high deformation rate were shifted and moved during the measuring processes by the weakly polarized probe. Both windward and leeward sides simultaneously expressed a slope towards each co-adjacent valley in the MFM maps and induced a statistical throbbing within a narrow band in the PSD curves. Thus, the MFM scanning mode was also analyzed and improved to obtain accurate MFM maps with low disturbances from the weak magnetic field of the probe. Swapping the order positions of the middle processes in the MFM scanning and adding a gliding step between them could offset the peak skewing of magnetic domains caused by the weakly polarized probe during MFM measurement process without incurring excessive replacement costs. Accumulative compression at a high rate (10 s) would crush magnetic domains into irregularly decreasing sizes with messy boundaries. This investigation provides an example of the complete relationships among deformations, magnetic domains, and magnetic properties.
使用原子力显微镜（AFM）观察了由Gleeble 3500热模拟系统制造的承受累积热压缩的无取向电工钢的磁畴。测量了沿探针自由方向的、由AFM探针与样品磁畴之间的磁力组成的分力，这些分力形成了磁畴的数值波动。通过检查功率谱密度（PSD）曲线来分析磁畴的波动。使用高灵敏度磁测量系统测量样品的磁滞曲线。磁力显微镜（MFM）图分析表明，一些磁畴被压缩成破碎和碎片化的形状，类似于变形晶粒的微观结构。同时，一些磁畴在热压缩过程中发生了重构，类似于动态再结晶微观结构。有意义的是，MFM探针在其弱磁场区域内移动并使测试样品的近端磁畴发生变形。在测量过程中，高变形率磁畴的峰值位置因弱极化探针而发生偏移和移动。在MFM图中，迎风面和背风面同时向每个相邻谷表达斜率，并在PSD曲线的窄带内引起统计脉动。因此，还对MFM扫描模式进行了分析和改进，以获得受探针弱磁场干扰小的准确MFM图。交换MFM扫描中间过程的顺序位置并在它们之间添加一个滑动步骤，可以抵消MFM测量过程中由弱极化探针引起的磁畴峰值偏斜，而不会产生过高的更换成本。高速率（10 s）的累积压缩会将磁畴压碎成尺寸不规则减小且边界杂乱的形状。本研究提供了一个变形、磁畴和磁性能之间完整关系的实例。
