摘要
研究制备了一种水性无铬锌铝涂料,并对涂料热稳定性、微观形貌、电化学性能及耐盐雾性进行测试与表征。研究表明,该涂料经过高温烧结后,涂层内部结构致密,片状结构锌粉和铝粉在涂层内部层层相叠,形成多道屏障,延长腐蚀介质在涂层内部的渗透路径。该涂料具有较好的热稳定性,经过7 d热稳定性测试,涂料的黏度和pH值均未发生明显变化。涂层自腐蚀电位(-1.043 V)低于Q235祼钢(-0.645 V),而且涂层自腐蚀电流(Icorr)4.82×10^(-6) A·cm^(-2)比Q235祼钢自腐蚀电流1.94×10^(-4) A·cm^(-2)降低两个数量级,腐蚀电阻从1.14×10^(2)Ω增加到4.43×10^(3)Ω,表明涂层的电化学腐蚀速率明显降低,可以为基材提供阴极保护。涂层经过600 h中性盐雾测试后,涂膜仍然保持较好的金属光泽,表面有很轻微白锈产生。
A waterborne chromium-free zinc-aluminum coatings material was prepared,tested and characterized for its thermal stability,microscopic morphology,electrochemical performance,and salt spray resistance.The research shows that after high-temperature sintering,the coatings have a dense internal structure.The flaky zinc powder and aluminum powder are layered inside the coatings,forming multiple barriers and prolonging the penetration path of the corrosive medium inside the coatings.The coatings have good thermal stability.After 7 d of thermal stability tests,the viscosity and pH value of the coatings did not change significantly.The self-corrosion potential of the coatings(-1.043 V)is lower than that of Q235 bare steel(-0.645 V),and the self-corrosion current(Icorr)of the coatings,4.82×10^(-6) A·cm^(-2),is two orders of magnitude lower than that of Q235 bare steel,1.94×10^(-4) A·cm^(-2).The corrosion resistance increases from 1.14×10^(2)Ω to 4.43×10^(3)Ω,indicating that the electrochemical corrosion rate of the coatings is significantly reduced and can provide cathodic protection for the substrate.After 600 h of neutral salt spray testing,the coatings film still maintains a good metallic luster,and there is very slight white rust on the surface.
作者
王祺轩
WANG Qi-xuan(Dalian University of Technology,Dalian 116024,Liaoning,China)
出处
《中国涂料》
2024年第12期45-49,共5页
China Coatings
关键词
无铬锌铝涂层
极化曲线
耐腐蚀性
chromium-free zinc-aluminum coatings
polarization curve
corrosion resistance
作者简介
王祺轩(2004–),男(汉族),辽宁大连人。本科在读,研究方向为材料成型及控制工程。
