论文部分内容阅读
采用快速水冷和空冷两种不同的轧后冷却制度得到强度范围在490~980MPa级的低碳微合金结构钢。用户外间断喷淋3.5%NaCl水溶液来模拟海洋大气腐蚀,对带锈试样进行电化学阻抗谱测试,并对锈层中腐蚀产物进行了观察分析。结果表明,不同强度级别的低碳微合金钢的长期耐腐蚀性能相近,并略优于商业化耐候钢09CuPCrNi。提高钢基体的组织均匀性有利于改善钢的初期腐蚀性能,在形成保护性锈层之前,基体腐蚀深度较小。少量颗粒细小相的存在。有利于提高钢基体与锈层的结合力;但大块珠光体的存在会危害钢的初期腐蚀性能,因此耐候钢09CuPCrNi初期腐蚀速率较大。
Low-carbon micro-alloyed structural steels with strength ranging from 490 to 980MPa were obtained by two different post-rolling cooling systems, water-cooled and air-cooled. The spray of 3.5% NaCl aqueous solution was used to simulate the marine atmospheric corrosion. The electrochemical impedance spectroscopy test was conducted on the samples with rust, and the corrosion products in the rust layer were observed and analyzed. The results show that the long-term corrosion resistance of low carbon microalloyed steels with different strength grades is similar and slightly better than that of commercial weathering steel 09CuPCrNi. Improve the homogeneity of the steel matrix is conducive to improving the initial corrosion of steel, the formation of protective rust before the matrix corrosion depth is small. The presence of a small amount of fine particles of small phase. Which will help to improve the bond strength between the steel substrate and the rust layer. However, the existence of large pearlite will endanger the initial corrosion performance of the steel, so the initial corrosion rate of the weathering steel 09CuPCrNi is larger.