海水介质中阴极保护用涂层钛阳极的制备及其性能研究

Development of Titanium Anode Coated with Mixed Metal Oxide for Catholic Protection in Seawater

为了提高钛阳极在阴极保护中应用的可靠性和使用寿命,用热分解方法制备了复合金属氧化物(MMO)涂层钛阳极,研究了阳极寿命与基材表面处理、涂敷量、温度、电流密度及涂层损耗率之间的关系。结果表明:基材喷砂增强了钛基体与涂层的结合力,增加涂敷量能够提高阳极寿命,而提高温度和电流密度对阳极寿命有不利影响,阳极涂层损耗率几乎为0。所研制的RuIrTiSnCo涂层钛阳极具有良好的电化学稳定性和较长的寿命,强化寿命达到96 h,约为次氯酸钠发生器标准的5倍,是海水介质外加电流阴极保护中比较理想的辅助阳极。

Titanium anode coated with mixed metal oxide(MMO) coating was prepared using thermal decomposition process so as to improve the durability and reliability of the titanium anode for cathodic protection.The relationship between the anode lifetime and surface treating of Ti substrate,coating amount,temperature,anode current density,and coating consumed rate was studied.The results indicated that substrate sandblast contributed to enhance the adhesion between the titanium substrate and the MMO coating,while increasing in the coating mass led to increased durability of the anode,and the coating consumed rate of the coated anode was almost zero.However,the increase in temperature and anode current density was harmful to the durability of the anode.In general,the MMO-coated Ti anode had good electrochemical stability and long durability,with the accelerated durability to be as much as 96 h,which was six times of that specified by GB 12176-90.Therefore the developed MMO-coated Ti anode could be used as promising auxiliary anode for cathodic protection in the presence of external electric current in seawater.