海洋用钢化学镀层耐蚀性的研究

发布时间：2018-07-07 08:18

  本文选题：Q235钢 + 化学镀　； 参考：《华北理工大学》2015年硕士论文

【摘要】：Q235钢是海洋中应用最为广泛的普碳钢,但海洋环境会对Q235钢造成腐蚀破坏,腐蚀到一定程度会引发海洋事故造成经济损失。所以了解Q235钢在海水中的耐蚀性并采取一定的防腐措施显得尤为重要。采用静态挂片实验方法研究Q235钢在模拟海水全浸区的耐腐蚀性能、腐蚀机理。结果表明:Q235钢在模拟海水全浸区达到均匀腐蚀时的腐蚀速率大约在0.041mm/a,属于耐蚀4~5级。腐蚀先以点蚀状态开始,随着腐蚀时间的增加,点蚀坑增加,并且逐渐连接起来,点蚀坑消失,形成均匀腐蚀层。腐蚀层分为两层,外锈层为γ-Fe OOH,内锈层为Fe3O4、α-Fe OOH、γ-Fe OOH、β-Fe OOH的混合物,腐蚀产物的形成主要是氧元素的扩散过程。为了提高Q235钢在海水中的耐蚀性,采用化学镀方法在Q235钢基体上镀Ni-P镀层。以化学镀Ni-P工艺参数中的络合剂和温度为主要考察因素,对化学镀Ni-P工艺配方进行了初步探索并通过正交实验进一步对工艺进行优化,得到的最佳工艺为:络合剂A 8g/L,络合剂B 10g/L,温度85℃。温度是对镀层沉积速率和镀层腐蚀速率影响最大的因素。采用电化学实验法,对Ni-P镀层及Q235钢的耐蚀性进行对比分析。Q235钢的自腐蚀电位-0.54V,极化电阻为704欧。Ni-P镀层的自腐蚀电位为-0.49V,极化电阻为1501欧。结果表明Ni-P镀层的耐海水腐蚀性能比Q235钢好。
[Abstract]:Q235 steel is the most widely used carbon steel in the ocean, but the marine environment will cause corrosion damage to Q235 steel, which will lead to economic loss caused by marine accidents to a certain extent. So it is very important to know the corrosion resistance of Q235 steel in seawater and take some anticorrosive measures. The corrosion resistance and corrosion mechanism of Q235 steel in simulated seawater immersion zone were studied by static strip hanging test method. The results show that the corrosion rate of WQ235 steel is about 0.041 mm / a in the simulated seawater immersion zone. With the increase of corrosion time, the pitting pits increase, and gradually connected together, the pitting pits disappear to form a uniform corrosion layer. The corrosion layer is divided into two layers, the outer rust layer is 纬 -Fe OOH, and the inner rust layer is the mixture of Fe 3O 4, 伪 -Fe OOH, 纬 -Fe OOH, 尾 -Fe OOH. The formation of corrosion products is mainly the diffusion process of oxygen elements. In order to improve the corrosion resistance of Q235 steel in seawater, Ni-P coating was deposited on Q235 steel substrate by electroless plating. With the complexing agent and temperature of electroless Ni-P plating as the main factors, the process formula of electroless Ni-P plating was preliminarily explored and optimized by orthogonal experiment. The optimum conditions are as follows: complex agent A 8 g / L, complex agent B 10 g / L, temperature 85 鈩，

本文编号：2104356