等离子喷涂制备直流接地极钢基体NiFe_2O_4防腐涂层  

Nickel Ferrite Coatings on Steel for DC Ground Electrode Prepared by Plasma Spraying Process

作　　者：祝志祥[1] 韩钰[1] 陈新[1] 马壮[2] 柳彦博[2] 

机构地区：[1]中国电力科学研究院电工与新材料研究所,北京100192 [2]北京理工大学材料学院,北京100081

出　　处：《中国表面工程》2012年第3期37-41,共5页China Surface Engineering

基　　金：中国电力科学研究院青年科研基金项目(DG84-11-003)

摘　　要：为提高常规碳钢直流接地极本体的耐蚀性能,采用固相反应法结合团聚-破碎法造粒合成出适合等离子喷涂的NiFe2O4粉体,利用等离子喷涂工艺在钢基体上制备NiFe2O4铁氧体涂层,并利用场发射扫描电镜、金相显微镜、X射线衍射仪以及涂层结合强度、电阻率、直流电解等测试方法,对NiFe2O4涂层的微观组织结构、物理电气和腐蚀性能进行了研究。结果表明:NiFe2O4涂层与基体的平均结合强度为21.8MPa,涂层平均电阻率约为3.60×10-2Ω.cm,且涂层耐电解腐蚀性能良好,腐蚀率约为1.86g/(A.a),可较好满足直流输电系统中接地极材料的服役要求,初步显示出等离子喷涂制备直流接地极用铁氧体环保防腐涂层的工艺可行性。To improve the corrosion-resistance of traditional steel DC ground electrode,pure NiFe2O4 powders were synthesized by solid state reaction.Via the powder granulation by grain aggregation and crushing,the NiFe2O4 ferrite coatings were prepared on the steel substrate through plasma spraying technology.The phase and microstructure of the coating were investigated by fileld emission scanning electron（FESEM）,metallographic microscopy and X-ray diffraction（XRD）,while the physical and electrical properties of the coating were measured by bonding strength,resistivity and DC electrolysis tests.The results showed that the mean adhesion strength of the coating was 21.8 MPa,and the average resistivity of NiFe2O4 coating was about 3.60×10-2 Ω·cm,as well as the electrolysis corrosion rate was about 1.86 g/（A·a）,which could satisfy the performance needs of DC ground electrode materials.This study also indicates the feasibility of corrosion-resistant ferrite coating preparation using plasma spraying technology.

关 键 词：固相反应法 铁氧体 NIFE2O4 电阻率 耐蚀 

分 类 号：TG174.442[金属学及工艺—金属表面处理]