【摘要】 采用线性极化测试、电化学阻抗谱和动电位极化等电化学测试技术并结合表面分析方法,研究了表面状态对X80管线钢在模拟土壤溶液(NS4)中的腐蚀行为影响。试验结果表明,随着表面粗糙度下降,其自然腐蚀电位向正向移动,腐蚀电流密度下降,即腐蚀速率减小;不同粗糙度的X80钢试样在NS4溶液中电化学阻抗谱表现为一个时间常数;随表面粗糙度的逐渐减小,电荷转移、电阻逐渐增大。微观形貌显示,试样表面腐蚀产物随着粗糙度的减小而逐渐减少。试样表面效应是引起不同粗糙度钢腐蚀差异的重要因素。更多还原

【Abstract】 Effect of surface state on the corrosion behavior of X80 pipeline steel in simulated soil solution( NS4) was investigated using the linear polarization,electrochemical impedance spectroscopy,potentiodynamic polarization and in combination with the surface analysis method. The test results show that with the decrease of surface roughness,the corrosion potential of the steel shifted toward the positive direction,and the corrosion current density,i. e.,corrosion rate,also decreased. The electrochemical impedance spectrum of X80 steel specimens with different roughness showed a time constant in NS4 solution. With the decrease of surface roughness,the charge transfer resistance increased gradually. The SEM results show that the amounts of corrosion products on the specimen surface decreased with the decrease of roughness. The surface effect is an important factor that causes the corrosion difference of the steel with different roughness.更多还原