摘要
采用低压冷喷涂的方法,在Q235碳钢上制备了以镍为主的镍-锌-氧化铝复合涂层。通过扫描电镜和EDS对涂层结构形貌进行了观察分析;通过天然海水浸泡和电化学阻抗的方法对其进行了腐蚀防护性能测试。涂层在海水中浸泡60d未产生红锈,模拟电路中涂层电阻在浸泡30d后仍然处于较高水平,表明复合涂层自身展现出了良好的腐蚀防护性能,并能够对碳钢基体起到腐蚀防护作用。涂层良好耐蚀性的主要原因有两点:一是涂层中的锌腐蚀产生致密腐蚀产物Zn(OH)2,能够起到封闭涂层贯穿孔隙,降低海水渗透的作用;二是涂层中的镍对Zn(OH)2具有稳定作用,能够降低其分解消耗,延长保护时间。
Nickel based coating reinforced with alumina and zinc was prepared on Q235 steel using low pressure cold gas dynamic spray method.Surface morphology and cross section of the coating were studied by SEM and EDS.Corrosion protection properties of this coating were tested with nature sea water immersion method and EIS.No red rust was observed on the specimen after 60 days immersion,and the simulated coating resistance after 30 days immersion retained at a rather high level,which means the coating has good corrosion resistant properties and the coating can protect steel substrate from corrosion.There are two main reasons for good corrosion resistance of this coating.First,the dense corrosion product Zn(OH)2 produced by Zn corroding blocks penetrated cracks in the coating and thus reduces the permeation of seawater.Second,nickel can stabilize the produced Zn(OH)2to extend its protecting time.
出处
《腐蚀与防护》
CAS
北大核心
2014年第8期829-832,860,共5页
Corrosion & Protection
关键词
镍基涂层
海洋腐蚀
冷喷涂
nickel matrix coating
marine corrosion
cold gas dynamic spray
