【摘要】 过去对耐候钢耐腐蚀性机理的研究,锈层初期生长因素考虑较少。模拟工业大气环境的周期浸润实验室加速试验,对试验钢进行了腐蚀失重分析;通过扫描电镜、X射线衍射、阳极极化等手段对锈层进行分析。主要研究耐候钢和碳钢的锈层组织和电化学性能。结果表明:腐蚀初期耐候钢的锈层组织成分以α-FeOOH为主;碳钢的锈层组织成分以Fe2O3为主。α-FeOOH晶体枝晶纤细,锈层致密,具有保护性;Fe2O3枝晶粗大,锈层疏松多孔,不具有保护性;耐候钢锈层具有钝化作用,对基体有很好的保护性。更多还原

【Abstract】 Accelerated dry-wet cyclic immersion tests were carried out at lab to simulate the immersed corrosion test of steels in industrial atmosphere,where the weight-losses of weath-ering steels and carbon steels were measured.Thus the composi-tions and electrochemical properties of the rusted layers on the weathering steels and carbon steels exposed to atmosphere were investigated,and the corrosion mechanism of the rusted layers were discussed based on analyses of scanning electron microsco-py,X-ray diffraction,and anode polarization testing.Results in-dicated that the rusted layers formed on the weathering steels dur-ing the initial corrosion period were mainly composed of a-FeOOH,and that on the carbon steels were mainly composed of Fe2O3.Moreover,the size of α-FeOOH crystal was very small,and the rusted layers were compact and had protective function.However,the size of Fe2 O3 crystal was very big,and the rusted layers were loose and porous,showing no protective function.In one word,the rusted layers on the weathering steels exposed to industrial atmosphere had passivation function and could protect the steels from corrosion.更多还原