| 引用本文: | 邢洪旋,胡宪伟,李继东,王耀武,赵辰旭.硅钢表面诱导共沉积钴铁软磁合金[J].中国表面工程,2024,37(3):185~194 |
| XING Hongxuan,HU Xianwei,LI Jidong,WANG Yaowu,ZHAO Chenxu.Induced Co-deposition of Co-Fe Alloy on Silicon Steel Surface[J].China Surface Engineering,2024,37(3):185~194 |
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| 摘要: |
| 针对硅钢的耐蚀性和软磁性能的问题，提出在硅钢表面诱导共沉积制备 Co-Fe 软磁合金镀层的工艺。采用 SEM、XRD 与 VSM 分析镀层微观形貌、相结构及软磁性能，并研究硫酸钴浓度、沉积电流密度、pH 以及酒石酸钠浓度等工艺参数对镀层微观结构以及镀层元素含量的影响。结果表明：硫酸钴浓度 20 g·L?1 ，酒石酸钠浓度 45 g·L?1 ，pH=8，电流密度 0.3 A·cm?2 为最优工艺参数，且镀层形貌致密，晶粒分布均匀；各个不同工艺参数下得到镀层的相结构均为 Co7Fe3，且择优取向无显著差别；当钴含量达到 65.11%时，饱和磁化强度达到 209 emu·g?1 ((A·m2 ) / kg)，矫顽力低于 4 Oe(1 Oe =79.6 A / m)，镀层具有最优的软磁性能。在 pH=5 的酸性溶液中，钴铁合金镀层的腐蚀电位正移了 0.012 V，自腐蚀电流密度降低为 2.86 μA·cm?2 ， 具有更好的耐蚀性能。通过对硅钢表面诱导共沉积 Co-Fe 软磁合金进行研究，为今后的硅钢资源防护利用提供了新思路。 |
| 关键词: 硅钢 诱导共沉积 钴铁合金 软磁性能 耐蚀性能 |
| DOI：10.11933/j.issn.1007-9289.20230611001 |
| 分类号:TG156；TB114 |
| 基金项目:国家自然科学基金（52374352）；辽宁省冶金工程省级重点实验室开放课题（2023KFKT-10） |
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| Induced Co-deposition of Co-Fe Alloy on Silicon Steel Surface |
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XING Hongxuan1，HU Xianwei2，LI Jidong1，WANG Yaowu2，ZHAO Chenxu1
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1.Provincial Key Laboratory of Metallurgical Engineering, Liaoning University of Science and Technology,Anshan 114051 , China ；2.School of Metallurgy, Northeastern University, Shenyang 110000 , China
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| Abstract: |
| Most scholars have investigated silicon steel coated with an insulating varnish and a magnesium silicate substrate covering the surface of silicon steel. However, before silicon steel is coated with an insulating varnish, it is exposed to an uncontrolled environment, which significantly increases the risk of corrosion. Therefore, investigating processes that enhance the corrosion resistance of silicon steel without affecting its soft magnetic properties is crucial. In this study, the process of preparing Co-Fe soft magnetic alloy plating by induced co-deposition on the surface of silicon steel is proposed to address the problems of corrosion resistance and soft magnetic properties of silicon steel. In addition, sodium saccharin(C7H8NNaO4S) is a commonly used additive in the plating process of sodium saccharin in the sulfur element; although the content of a very small amount of the plating layer and its soft magnetic properties have a negative impact, non-toxic and non-polluting sodium tartrate, instead of sodium saccharin, was used in this study. After preparing the Co-Fe soft magnetic alloy coating, the microstructure of the coating and change of elemental content were studied in detail using scanning electron microscopy and energy dispersive spectroscopy; the phase structure composition of the coating and peak diffraction intensity were analyzed using X-ray diffraction; and the soft magnetic properties were investigated using the hysteresis line measured by vibrating-sample magnetometry. The process parameters such as cobalt sulfate concentration,deposition current density, pH, and sodium tartrate concentration were optimized step by step by the above test methods, and the optimal process parameters were selected and the optimal coating structure was constructed by analyzing the microstructure of the plating layer and the variation of the elemental content of the plating layer. The results show that the optimum process parameters are 20 g·L?1 cobalt sulfate, 45 g·L?1 sodium tartrate, pH=8, and 0.3 A·cm?2 current density, and the plated layer has a dense morphology and uniform grain distribution. In addition, the phase structure of the plated layer was Co7Fe3 with no significant difference in the preferred orientation for each process parameter. Cobalt content that is excessively high or low in the coating has a negative effect on the soft magnetic properties; when the cobalt content reaches 65.11%, the saturation magnetization strength reaches 209 emu·g?1 ((A·m2 ) / kg), the coercivity is below 4 Oe(1 Oe=79.6 A / m), and the plating has optimal soft magnetic properties, which meets the national requirements of the soft magnetic properties of silicon steel. In the corrosion test, the corrosion solution used in previous studies was a NaCl solution with a mass fraction of 3.5%, but the working environment of the silicon steel of the transformer core was exposed to air or was in a harsh acidic environment. Therefore, the corrosion solution we selected was a vented acidic solution (HCl) with pH 3, 4, and 5, and vented deionized water, to simulate the actual production and storage environment and to ensure that the oxygen was saturated. The test studies on corrosion performance revealed that the corrosion potential of cobalt-iron alloy plating was positively shifted by 0.012 V and the self-corrosion current density was reduced to 2.86 μA·cm?2 in pH = 5 acidic solutions, which provided more optimized corrosion resistance. Compared with the traditional silicon steel surface coating, insulating varnish, and magnesium silicate substrate research, the electrodeposition of Co-Fe soft magnetic alloy is a new type of protection method, and the future surface treatment of silicon steel has reference significance. |
| Key words: silicon steel induced co-deposition cobalt-iron alloy soft magnetic properties corrosion protection |
