A real-time monitor method based on Electrochemical Noise (EN) was set up to study the atmospheric corrosion of aluminum alloy. The electrolytic cell was designed and made accordingly. Inshore, oceanic atmosphere and contaminative industrial atmosphere with neutral pH value, constant temperature and humidity were simulated.Using the established method atmospheric corrosion of the aluminum alloys LY12CZ and LC4CS was studied. The electrochemical noise resistance Rn and the slopes K of the potential power density spectrum (PDS) were gotten in EN test. The corrosion behavior of aluminium alloy in simulated atmosphere, and influence of Cl—、NO3— and SO42— in corrosion process of the aluminium alloys (LY12CZ and LC4CS) were studied with corrosion rate and corrosion type.

Series of accelerated corrosion tests were conducted in simulated marine atmosphere to study initial corrosion of LY12 aluminum alloy (corresponds to USA 2024) at different humidity. The change of corrosion morphology, weight gain, maximum pitting depth and electrochemical parameters (Corrosion Potential, AC Impedance) were inspected in corrosion course. Results showed that for Cl- deposition about 1 mg/dm2 and temperature 25℃, LY12 aluminum alloy did not erode under relative humidity 60%, can develop pitting corrosion in 31days above relative humidity 70%, erodes seriously not only in weight gain, but also in pit depth above relative humidity 90%. In marine atmospheric, the relationship of LY12 weight gain-time at different humidity fitted Model Boltzman. For pitting surface of LY12 at different humidity in marine atmosphere, Nyquist Graph was single arc of capacitance resist and the shape of arc was identical with retractile real part.

The effects of phosphorus on corrosion resistance of low carbon steels have been investigated by cyclic corrosion test、SEM and micro-Raman analysis. The results indicate that phosphorus can increase corrosion resistance of low carbon steels especially at the early stage of atmospheric corrosion. The reason is :with the effect of water and oxygen, the phosphorus enriched on the face of steels was hydrolyzed ,then phosphate was formed .This kind of phosphate cover on the cranny and holes in rust and resist water and oxygen’s passing. Moreover, the can accelerate the air oxidation of Fe2+ to Fe3+ and the formation of stable rust . As a result , the corrosion resistance of high phosphorus steels was improved .

By employing Mott-Schottky analysis in cinjumction with the point defect model(PDM),we compared donor density and donor diffusion coefficients in the passive films formed on the surface of nanocrystallized bulk 304 stainless steel(NB304ss) and cast 304 stainless steel (304ss )in 0.05 mol/L H2SO4+ 0.25 mol/L Na2Ao4 solution. The donor density at the metal/film interface of the NB304SS was lower than that at the metal film interface of the cast 304SS.Based on the MOtt-Schottky analysis, an exponential relationship between donor density and formation potentials of the passive films on the NB304SS and the cast 304SS was built up. The results showed that the donor diffusion coefficients in the passive film formed on the surface of NB304SS was built up. The results showed that in the cast 304SS.The lower donor density restrained jthe electrochemical reaction in the passive film and improved the stability of the passive film. That is the reason why the passive film formed on the NB304SS was more protective.

By means corrosion tests, polarization curve, X-ray photoelectron spectrum(XPS), atomic force microscope(AFM), the protective film on carbon steel formed with phosphate acid and zinc salt was researched. The results show that this pre-filming agent can form compact film on carbon steel. The film structure is chelated phosphate deposit grain with 50 nm. The composition of the film is consisted of 55% O\16%Ca\14%P\5%Zn\7%C安定2%Fe(mol%)

The effect of Ce-ion and La-ion inhibiting the corrosion of steel in NaCl solution has been investigated by salt water droplet test, corrosion production micro-analysis and electrochemistry test. The potential-pH diagram of RE-H2O was also used to investigate the chemical stability of various kinds of RE compound. The results showed that oxide and hydrate of RE deposited in the cathodal area where the pH value was relatively high and inhibited the corrosion of steel by blocking the transmission of O2 and electron between the cathodal area and solution. The potential-pH diagram and thermodynamics calculation showed the compound of Ce was more stable than compound of la in theacid solution and suggested that the ability of inhibition corrosion of Ce-ion is better than that of la-ion.

Self-assemble momolayers of different schiff bases were formed on a copper surface.by self-assemble technology. The effects of corrosion inhibition efficiency on Schiff base structure were studied by electrochemistry impedance spectrum(EIS),scanning electron microscopy (SEM) and quantum chemical calculation. The results showed that the Schiff bases mainly accepted electrons while reacting and the nitrogen atom in the -C=N- groups and the oxygen atom in -OH groups were the mainly reaction groups. If the hydrogen atoms at aromatic rings of Schiff bases were substituted by abundant electron groups, the corrosion inhibition efficiency were improved and the closer the abundant electron groups to -C+N- groups ,the higher the corrosion inhibition efficiency.

The alloys and corrosion products of the Pb - Sn alloy solders, existing in bronxes excavated from Jiuliandu site during Warring States Period, were analyzed by using techniques of energy spectrum, X- ray powder diffraction, X - ray fluorescence spectrometry and metallurgical analysis , etc. The analysis indicated that corrosive products that were composed of PbCO3, Pb and SnO2 were compact and firm, and the buried circumstance, with the neutral pH and the high content of HCO3-,was relatively isolated, which had cooperated to hinder the corrosion of Pb - Sn solders to keep bronzes in good figure.

Electrochemical polarization curves, Atom Force Spectroscopy and Electronic Probe Measurement Analysis were used to study the sensitivity of biofilm on Q235 steel to MDOPD in the culture medium inoculated sulfide-reducing bacteria (SRB). The experiment results show that surface status of Q235 steel electrode and corrosion reaction facilitated by SRB were decreased greatly owing to the adsorptive film of MDOPD. It is difficult for metabolized product of SRB in medium and corrosion production to deposit directly on carbon steel surface, then the acceleration effect of SRB medium and course including acid soak to corrosion was reduced markedly.At the same time, it is hardly possible for SRB in medium to metabolize on carbon steel surface and this would decrease the possibility for SRB to assist corrosion in the medium.

In order to see about anti-corrosion of silanization pretreatment on aluminium alloys surface, YL12 Al aloys surface were treated with γ- glycidoxypropyltrimentoxysilane(GPTMS),bis- [triethoxysilylpropyl] tetrasulfide(BTSPS) and bis-1,2-(triethoxysilyl) - ethane (BTSE)by dip-coating process. GPTMS and bis - silane films layer were cured at 100 ℃ for 60min and 130℃ for 60min respectively. Corrosion resistance of various silane silanization films layer were tested with potentiodynamic scan (PDS) and electrochemical impedance spectroscopy (EIS)in 3.5mass% NaCl solution and compared with that of chromated conversion coatings. The results show that the corrosion resistance of bis - silanization film layer exceeded that of organofunctional silane, the antiresistance of BTSPS silanization film layer exceeded that of all others.

A silver-silver chloride reference probe has been made by electrolytic method and its structure and ingredient is characterized with EPMA. A series of its performances are studied. The results show that the silver-silver chloride reference probe has good properties such as stability and precision in 3.5%NaCl, the little potential difference between two probes in long term, the response property to temperature and the concentration of Cl－, antipolarization. Thus the probe studied probably can be used as sense organ in the precision instrument of electrochemical measurement.

This paper mainly analyses the cause and principle of the failure of thin - film evaporator unit for purification processes in producing caprolactam. The device was forced to shutdown because of the decrease of wall thickness from 13.00 mm to 6.58 mm. The results of microstructrue and chemical composition analysis showed the failed component is eligible 304L stainless steel. By means of scanning electron microscopy it was found that there were corrosion ditches along the line of liquid flow and loose corrosion prduction layer on the surface of inner wall. Energy spectrum analysis showed the selective dissolution of elements Fe , Ni resulted in enrichment of Cr in the thinner corrosion production layer. According to the results of sample analysis and investigation of the operating conditions, it is confirmed that erosion - corrosion caused by high - speed liquid film containing organic acid is the main cause of the failure of the inner wall, and the corrosion thinned rate was accelerated after improving processing capacity. Moreover, corrosion resistance of stainless steels 304L,316,321 in acidic caprolactam solution was analyzed by potentiodynamic polarization curve measurement. It was confirmed that 316 stainless steel possessed better corrosion resistance to liquid flow.

Recent developments in carbon dioxide corrosion of N80 well tube steel,the pivotal effect factors while corrosion happening and directions in forward research are reported in the article. At present, some important results are found,such as there will be a peak value of corrosion velocity during temperature，CO2 partial pressure,velocity of flow increasing;the structure of corrosion production scale effects on the process and formation of corrosion and only continuous,compact and high cohesion scale can restrain corrosion aggravating;reaction mechanism becomes more complicated when oil or H2S is added to the medium resulting in transmission process and interface state changing.Specially, it should be studied systematically that effects of the varieties of corrosion parameters on the structure and mechanical properties of corrosion scale.Henceforth,the keystones are detailing the sensitivity region that corrosion parameters effect on corrosion velocity,improving the method of dynamic simulate test,probing into the dynamic electrochemistry in-situ measurement technique.