杨迈之
,
陈利
,
蔡生民
中国腐蚀与防护学报
采用光电化学方法对纯铁在ｐＨ＝８．４的硼酸－硼砂缓冲液中的孔蚀现象及缓蚀剂ＰＣ－６０４的作用进行了研究。结果表明，加入不同量的缓蚀剂后，铁表面饨化膜的禁带宽度没有发生变化，但是光电流信号却随缓蚀剂量的增加而增大了。从光电流暂态谱的研究中首次提出了钝化膜的膜参数的概念，并用以衡量钝化膜的抗孔蚀能力。
关键词:
光电化学
,
Iron
,
Pitting
,
Inhibitor
龚敏
,
邹振
,
郑兴文
,
黄文恒
,
赵芳
腐蚀与防护
根据实际的制盐工艺条件,使用单因素试验和均匀试验,采用电化学测试方法,研究了2205双相不锈钢在不同的S2-浓度、CO2-3浓度、pH值和流速的盐卤介质中的腐蚀行为.结果表明,在盐卤介质中S2-浓度和pH值对2205DSS的耐蚀性能影响较大,而C22-3浓度和流速对其影响较小.
关键词:
2205DSS
,
卤水环境
,
点蚀
,
均匀设计试验
,
电化学测试
K.Jafarzadeh
,
T.Shahrabi
材料科学技术（英）
In this research, EIS (electrochemical impedance spectroscopy) technique was utilized to study the pitting corrosion behaviour of AA5083-H321 aluminum-magnesium alloy in 3.5% NaCl solution. Impedance spectra were obtained during 240 h of exposure of the sample to the test solution. The surface and cross-section of the samples were studied by scanning electron microscopy (SEM) and EDAX (energy dispersive analysis of X-ray) analysis. The results indicated that as the resistance of the passive layer on intermetallic particles is very small, this parameter on the sample surface layers is controlled by that of pure passive layer. However, the capacitors in the proposed equivalent circuit are replaced with the constant phase elements (CPE), due to non-uniformity and occurrence of pitting corrosion on the surface. The outward diffusion of Al+3 ions through the passive layer and the thickening of this layer cause the impedance decrease in the first 24 h and increase afterwards. The detachment of intermetallic particles from some of pits and the accumulation of the corrosion products inside some others are factors that prevents the continuation of cathodic reactions on the top of the intermetallic particles.
关键词:
Corrosion
,
null
,
null
,
null
,
null
Junwei WU
,
Xiaogang LI
,
Cuiwei DU
,
Song WANG
,
Yiquan SONG
材料科学技术（英）
Corrosion behaviors of X70 steel were studied by means of electrochemical experiments and morphology observation. First, through potentiodynamic polarization in solution of various Cl- ions concentration, it was found that Epit began to appear in solution of Cl¬- concentration above 0.1 mol/L, and there was a critical point of Cl- concentration between 0.05 mol/L and 0.1 mol/L, below which the extent of pitting and general corrosion were trivial, while in solution of Cl- concentration above 0.1 mol/L, general and pitting corrosion became greater as the increasing of Cl- concentration. All of them were confirmed by the SEM observations after anodic polarization. Second, via the potentiodynamic polarization curves of X70 steel in 0.5 mol/L Cl-solution with 0, 0.05, 0.5 and 1 mol/L SO¬42- ions, it was found SO¬42- ions were able to inhibit corrosion aroused from Cl-1 ions, accordingly a model was set up to describe the process. In addition, to further explore the inhibited effect of SO¬42- ions, EIS was used in solutions of different Cl- and SO¬42- concentrations, the results revealed that the electrochemical resistance has a relation with the [SO42-]/[Cl-], that was, the bigger the value of [SO42-]/[Cl-], the greater the electrochemical resistance.
关键词:
X70 steel
,
null
,
null
,
null
,
null
Chunlin HE
,
Changsheng LIU
,
Fengqin LI
,
Qingkui CAI Zhiming SHI
,
Liqing CHEN
,
Jing BI
材料科学技术（英）
The influences of volume fraction and particle size of SiC particulate reinforcements on the corrosion characteristics of SiCp/2024 Al metal matrix composites in aerated 3.5 wt pct NaCl aqueous solution were investigated. The electrochemical behavior was investigated by potentiodynamic polarization and electrochemical impedance spectroscopy, the general corrosion behavior of the composites was studied further by immersion tests. The results showed that pitting susceptibility was about the same for the composites and the alloy. The corrosion potentials were also independent of SiC phase. The corrosion resistance for the composites decreased as the volume fraction increased or particle size decreased.
关键词:
SiCp/2024Al matrix composites
,
null
,
null
