Mn含量对NdFeB磁体表面Al基防护涂层性能影响的研究  

Effect of Mn content on the properties of Al-based protective coatings on NdFeB magnets

作　　者：李慧[1,2] 鲁飞[1,2] 刘树峰[1,2] 张帅[1,2] 温永清 刘小鱼[1,2] LI Hui;LU Fei;LIU Shufeng;ZHANG Shuai;WEN Yongqing;LIU Xiaoyu(State Key Laboratory Baiyunobo Rare Earth Resource Researches and Comprehensive Utilization,Baotou Research Institute of Rare Earths, Baotou 014030, China;National Engineering Research Centre of Rare Earth Metallurgy and Functional Materials,Baotou 014030, China)

机构地区：[1]包头稀土研究院白云鄂博稀土资源研究与综合利用国家重点实验室,内蒙古包头014030 [2]稀土冶金及功能材料国家工程研究中心,内蒙古包头014030

出　　处：《功能材料》2022年第3期3124-3129,共6页Journal of Functional Materials

基　　金：内蒙自治区自然基金资助项目(2020MS0515);科技兴蒙行动专项资助项目(XM2020BT01)。

摘　　要：采用等离子喷涂工艺在烧结NdFeB磁体表面喷涂不同Mn含量(Mn=0~30%(质量分数))的Al基防护涂层。利用X射线衍射仪、扫描电镜、显微硬度仪和多功能材料表面性能测试仪分析涂层物相组成、表面堆积状态、硬度和结合强度;采用动电位极化曲线和中性盐雾腐蚀试验测试涂层耐腐蚀性能,研究Mn含量对涂层防护性能的影响。结果表明,随着Mn含量的增加,涂层中硬脆Al-Mn系金属间化合物相逐渐增多,导致涂层硬度增加,高锰含量w(Mn)=25%,30%(质量分数)涂层表面出现裂纹。其中Mn含量为20%(质量分数)的喷涂防护涂层表面致密,无明显裂纹、孔隙缺陷,硬度值为400 HV以上,结合力>19 N,耐盐雾腐蚀时间达300 h,可以满足磁体表面高强耐蚀涂层防护需求。Al-based protective coatings with different Mn contents(w(Mn)=0-30 wt%)are sprayed on sintered NdFeB magnets by plasma spraying.The phase composition,surface stacking state,hardness and adhesion strength of the coating are characterized by X-ray diffraction(XRD),scanning electron microscope(SEM),micro-hardness tester and multi-functional surface property tester.The corrosion behavior of the coating is measured by potentio dynamic polarization tests and neutral salt spray test.The results show that the hard brittle Al-Mn intermetallic compound phase in the coating increases gradually with the increase of Mn content,which leads to the increase of hardness of the coating and the appearance of cracks on the surface of the coating with high Mn content(w(Mn)=25 wt%,30 wt%).The surface of the coating with the Mn content of 20 wt%.is compact,without obvious crack and pore defect,the hardness is over 400 HV,the adhesion strength is over 19 N,and the salt spray corrosion time is over 300 h,which could meet the need of the high-strength corrosion resistance coating on the surface of the magnet.

关 键 词：钕铁硼 等离子喷涂 Al基涂层 耐蚀性 

分 类 号：TB37[一般工业技术—材料科学与工程]