纳秒激光微刻蚀取向硅钢的形貌特征及磁性能

Morphology Features and Magnetic Properties of Micro-ablating Oriented Silicon Steel by Nanosecond Laser

为有效降低取向硅钢铁损、改善其磁性能,采用红外纳秒激光对取向硅钢进行微刻蚀试验。利用3D共聚焦显微镜、扫描电镜与能谱仪研究典型工艺参数下的硅钢表面烧蚀形貌特征及表面质量,利用铁损仪测试不同刻蚀参数下取向硅钢的铁损、相对磁导率等磁性能参数及动态磁滞回线,对比分析刻痕前后磁性能的变化行为、规律及磁滞特性。结果表明:激光刻痕后,硅钢的铁损、相对磁导率、矫顽力及剩磁等性能得到明显改善,铁损的改善表现在高磁感强度下、相对磁导率的改善表现在低磁场强度下,回线特性得到优化。扫描速度为800 mm/s、脉冲能量为0.25mJ时,刻痕边界呈近似规则的“波浪线”,且刻痕表面质量较高,铁损降低高达11.6%、剩磁降低12.8%等;刻痕后相对相对磁导率明显提高,提高约为5.7%~15.16%,最大可达2.598×10^4。激光频率与扫描速度的耦合关系是影响刻痕边界形状与磁畴细化效果的重要因素。

In order to effectively reduce the loss of oriented silicon steel and improve its electromagnetic properties,the oriented silicon steel was scribed by the infrared nanosecond laser.The ablation morphology and surface quality of silicon steel with typical process parameters were studied by 3D confocal microscopy,scanning electron microscopy and energy dispersive spectroscopy.The iron loss meter was used to measure the electromagnetic properties of oriented silicon steel after laser scribing with different parameters,such as iron loss,electromagnetic properties and dynamic hysteresis loop.The variation behavior,law and hysteresis property of electromagnetic properties before and after scribing were compared and analyzed.The results show that the iron loss,permeability,coercivity and residual magnetic flux density of silicon steel are obviously improved after laser scribing.The improvement of iron loss is manifested under high magnetic induction.The improvement of permeability is reflected in the low magnetic field intensity.The loop characteristic was optimized.When the scanning speed is 800 mm/s and the pulse energy is 0.25 mJ,the scribe boundary is close to regular“wavy line”,and the high surface quality of the scribe is shown.The iron loss decreases by 11.6%,and the residual magnetic flux density decreases by 12.8%.After the scribe,the relative magnetic permeability obviously increases by 5.7%to 15.16%,and the maximum is 2.598×104.The coupling relationship between the laser frequency and the scanning speed is an important factor affecting the shape of the notch boundary and the effect of magnetic domain refinement.