装备典型材料循环盐雾加速腐蚀行为与机理研究
Accelerated Corrosion Behavior and Mechanism of Typical Material for Equipment by Cyclic Salt-Spray Test
赵朋飞 1郭文营 1文磊 2吴俊升 2魏小琴3
作者信息
- 1. 航天科工防御技术研究试验中心,北京 100854
- 2. 北京科技大学,北京 100083
- 3. 西南技术工程研究所,重庆 400039
- 折叠
摘要
目的 研究装备典型材料在循环盐雾试验条件下的加速腐蚀行为与机理,建立快速分析和表征碳钢腐蚀性能的试验方法.方法 通过实施模拟海洋大气环境腐蚀效应及作用特点的循环盐雾加速腐蚀试验,采用SEM、XRD及电化学测试等手段,表征和分析样品腐蚀质量损失、腐蚀形貌、腐蚀产物成分、腐蚀电压、腐蚀电流密度及阻抗等腐蚀性能随暴露时间的变化规律,归纳碳钢的加速腐蚀行为和电化学机理.结果 碳钢样品腐蚀质量损失动力学符合幂函数规律,腐蚀速率整体呈现先升高、再降低的变化趋势.腐蚀产物为疏松外层与相对致密内层组成的准双层结构,整体呈现从疏松剥落到逐渐增厚致密的变化过程,成分以铁的氧化物和羟基氧化物为主.极化曲线拟合的腐蚀电流密度呈现先波动增加、后减小的变化趋势,腐蚀电位则围绕中枢值上下波动.电化学阻抗谱由 2 个容抗弧组成,后期容抗弧中低频区的直线表示出 Warburg阻抗的典型特征.结论 循环盐雾加速腐蚀试验能够较为全面地描述碳钢材料的加速腐蚀行为与机理,为进一步研究装备典型材料室内外腐蚀试验相关性提供条件.
Abstract
The work aims to study the accelerated corrosion behavior and mechanism of typical materials for equipment under the cyclic salt-spray test conditions,and establish test methods for analyzing and characterizing the corrosive properties of carbon steel.Cyclic salt-spray accelerated corrosion tests were performed to simulate the corrosion effect and action process characteristics of marine atmospheric environment.By such instruments as SEM,XRD,electrochemical measurement etc.,the corrosive properties of specimens with different exposure time,such as corrosion weight loss,corrosion morphology,corrosion product composition,corrosion potential,corrosion current density,impedance were characterized and analyzed and the acceler-ated corrosion behavior and mechanism of carbon steel were summarized.The corrosion weight loss of the carbon steel speci-men conformed to the power function law,the corrosion rate increased and then decreased.The corrosion product was a quasi-bilayer structure consisting of a loose outer layer and a relatively dense inner layer,which presented a variation from loosening and falling off to thickening and becoming dense gradually.The chemical constituents of corrosion products mainly contained oxides and oxyhydroxides of Fe.Corrosion current density fitted with polarization curves showed the variation trend of rising in fluctuation and then descending,and the corrosion potential fluctuated up and down around the central value.The electrochemical impedance spectroscopy was composed of two capacitive loops and the low and intermediate area of capacitive loops showed a straight line,which represented typical characteristics of Warburg impedance.The corrosion behavior and mechanism of carbon steel can be characterized more comprehensively by cyclic salt-spray accelerated corrosion test,which provides conditions for investigating correlation between indoor and outdoor corrosion tests of typical materials for equipment.
关键词
循环盐雾试验/碳钢/腐蚀质量损失/腐蚀形貌/电化学测试/腐蚀行为与机理Key words
cyclic salt-spray test/carbon steel/corrosion weight loss/corrosion morphology/electrochemical test/corrosion behavior and mechanism引用本文复制引用
基金项目
技术基础科研项目(JSHS2016204B002)
出版年
2024
NETL
NSTL
万方数据