烧结NdFeB永磁体表面TiO_2/聚氨酯基复合涂层的制备及耐蚀性研究  

Preparation and Corrosion Resistance of TiO_2/Polyurethane Coatings on Sintered NdFeB Permanent Magnets

作　　者：徐吉林[1,2] 张鹏[2] 罗军明[2] 陆磊[1] 钟震晨[3] 

机构地区：[1]江西省科学院江西省钨铜新材料重点实验室,南昌330029 [2]南昌航空大学材料学院,南昌330063 [3]江西理工大学稀土磁性材料及器件研究所,赣州341000

出　　处：《材料导报》2016年第10期57-60,共4页Materials Reports

基　　金：国家科技支撑计划项目(2012BAE02B01);江西省铜钨新材料重点实验室开放基金(2013-KLP-01)

摘　　要：采用阴极电泳沉积在烧结NdFeB永磁体表面制备了TiO_2纳米颗粒增强的聚氨酯涂层,研究了电泳沉积过程中电流密度的变化趋势和电泳液中二氧化钛颗粒浓度对复合涂层的表面形貌、粗糙度、接触角、显微硬度和耐蚀性的影响。结果表明,电泳沉积过程中电流密度随着时间的延长而降低,大致可分为3个阶段;二氧化钛颗粒可均匀弥散地分布在聚氨酯基体中,随着电泳液中二氧化钛浓度的增加,复合涂层中镶嵌的颗粒越多,导致表面粗糙度和硬度增大,而接触角降低;复合涂层可大幅度降低NdFeB试样在H_2SO_4溶液中浸泡的质量损失,且二氧化钛浓度越大,质量损失越小,即纳米二氧化钛颗粒的掺入进一步提高了NdFeB永磁体的耐蚀性。A series of TiO2nanoparticles-reinforced polyurethane coatings were prepared on the surface of sintered NdFeB ermanent magnets via cathodic electrophoretic deposition.The variation tendency of the current density during the electrophoretic deposition process was studied,and the TiO2 concentration dependences of composite coating′s surface morphology,surface roughness,contact angle,microhardness and corrosion resistance were investigated.The results showed that the current density decreased over time and the curve of current density-time could be devided into three stages.The TiO2 particles were uniformly and dispersively distributed in the polyurethane matrix,and the number of the particles inside the composite coatings increased with the rising TiO2 concentration,which resulted in the increase of the surface roughness and microhardess and the decrease of the contact angles of the composite coatings.The weight loss of the NdFeB magnets immersed in the H2SO4 solution decreased substantially due to the exsitence of the composite coa-tings,and the weight loss further decereased with the rising TiO2 concentration.In other words,the addition of TiO2 particles into polyurethane coating can further promote the corrosion resistance of NdFeB magnet.

关 键 词：烧结NDFEB永磁体 电泳沉积 纳米二氧化钛 聚氨酯涂层 

分 类 号：TG174.4[金属学及工艺—金属表面处理]