扰动溶液中模拟剥离涂层底部Q345钢阴极极化水平

Cathodic Polarization Level of Q345 Steel beneath Simulated Disbonded Coating in Agitated Solution

利用分段电极测量了阴极保护下矩形模拟剥离涂层底部Q345钢的电位和电流分布,研究了浓度为0.5 mol/L的静态溶液及充氧动态溶液中,不同阴极保护电位、缝隙宽度以及漏点尺寸条件下缝内阴极极化水平。结果表明,充氧扰动作用减弱了缝内阴极极化水平,致使钢片在扰动溶液环境中比在静态溶液需要更高水平的阴极保护,才能有效抑制缝内金属腐蚀。缝隙宽度和漏点尺寸对充氧扰动改变缝内极化水平的影响明显。

Potential and current distributions in a cathodically polarized crevice between a simulated disbonded coating and segmented Q345 steels were measured, and the cathodic polarization level in crevice was studied at various level of cathodic protection, and various size of crevice thickness and holiday. The results revealed that agitation decreased the polarization level in crevice, leading to the fact that a higher level of cathodic protection was required to inhibit the metal corrosion in crevice in agitated solution, compared with that in static solution. Crevice thickness and holiday size had significant influence on the phenomenon of agitation weakening the polarization level in crevice.