带腐蚀产物超高强度钢的电化学行为  

ELECTROCHEMICAL BEHAVIORS OF ULTRA HIGH STRENGTH STEELS WITH CORROSION PRODUCTS

作　　者：孙敏[1] 肖葵[1] 董超芳[1] 李晓刚[1] 钟平[2] 

机构地区：[1]北京科技大学腐蚀与防护中心,北京100083 [2]北京航空材料研究院,北京100095

出　　处：《金属学报》2011年第4期442-448,共7页Acta Metallurgica Sinica

基　　金：国家科技部基础条件平台建设项目2005DKA10400;国家自然科学基金项目51001012资助~~

摘　　要：采用动电位极化、电化学阻抗、扫描电镜(SEM)、扫描Kelvin探针(SKP)和Raman光谱研究了300M和AerMet100超高强度钢盐雾实验后试样的电化学行为.结果表明,300M钢在盐雾实验中生成的腐蚀产物为γ-FeOOH和Fe(OH)_3;AerMet100的腐蚀产物为β-FeOOH,Fe_3O_4和γ-Fe_2O_3.Fe_3O_4和γ-Fe_2O_3较γ-FeOOH致密,更加有效阻碍了O_2和Cl^-的扩散,对基体起到很好的保护作用.随盐雾时间的延长,2种钢的腐蚀电位均降低,腐蚀电流密度均增大,阳极溶解作用增强;300M钢的腐蚀产物电阻随腐蚀产物的集聚而增大,随脱落而减小;带腐蚀产物的AerMet100的电化学过程受扩散作用控制,Warburg阻抗随盐雾进行而增大.盐雾实验后2种超高强度钢的Kelvin电位值较未盐雾时高0.5-0.6V,且整个测试面的Kelvin电位值随盐雾时间的延长而逐渐不均匀.300M的腐蚀产物保护作用较差,AerMet100的耐蚀性和腐蚀产物的保护性能优于300M.The electrochemical behaviors of ultra high strength steels,300M and AerMet 100, with corrosion products which were formed during salt spray test were studied using potentiodynamic polarization curve,EIS,SEM,scan Kelvin probe（SKP） and Raman spectroscopy.The results show that the corrosion products on the steel 300M areγ-FeOOH and Fe（OH）_3,and those on the steel AerMet 100 areβ-FeOOH,Fe_O_4 andγ-Fe_2O_3 after salt spray test.Because of the compact characterization, Fe_3O_4 andγ-Fe_2O_3 have a better protection property for substrate by hindering the permeation of O_2 and Cl^-.The corrosion potentials shift negatively and corrosion current densities become larger with increasing salt spray time,meaning a faster rate of anodic dissolution for these two steels.After salt spray test,the values of Kelvin potential for the two steels are 0.5-0.6 V positive than those before tests,and more uneven.For 300M,the corrosion resistance of rust layer becomes larger/smaller with the corrosion productions gathering/drapping on/from the samples.The electrochemical reaction for AerMet 100 is diffusion-controlled process and the value of Warburg impedence which expresses the diffusion-hindering effect becomes larger.The corrosion resistance and protection ability of corrosion products for steel AerMet 100 are better than those of steel 300M.

关 键 词：超高强度钢 扫描KELVIN探针 RAMAN光谱 腐蚀产物 微区电化学 

分 类 号：TG172.4[金属学及工艺—金属表面处理]