The local potential and pH along a crevice simulating disbonded coating on pipelines were measured using microelectrodes.The effectiveness of cathodic protection (CP) in the local environment and the effects of applied cathodic potential, geometry of the crevice and solutio conductivity were investigated. The results showed that the IR drop in the disbondment mainly occurred in the vicinity of the opening. The distance effectively protected by CP increased with the decreasing applied potential. However, hydrogen evolution had a reverse effect when an overprotection potential was applied. The additional effct of CP was shown to be the modification of the local environment , such as increase of pH and conductivity of solution, which was beneficial to corrosion controlling as well as direct polarization of the exposed steel at the holiday.

The experiment was carried out on the systematic contrast of the Fe3Al, Fe3Al(75vol%)/ZrO2 and Fe3Al（50vol%）/ZrO2 samples .With the methods of electrochemical impedance spectroscopy(EIS), polarization and SEM. Through establishing electrical model of the metal/solution and equivalent circuit(EC),it proved that the corrosio resistance of the composites is worse than the single-phase Fe3Al material after immersed in seawater for 1day. however, with the immersion time increasing , the corrosion rate of Fe3Al（50vol%）/ZrO2 sample decreased dramatically because of its special microstructure. finally the corrosion resistance of Fe3Al（50vol%）/ZrO2 was proved to be the best of the three materals.

Microstructure and phase constituent of magnesium-aluminum alloys adding different aluminum content (3.4mass%, 9.3mass%, and 20.7mass%)were investigated utilizing the scanning electron microscopy (SEM) equipped with energy-dispersive analysis of x-ray (EDAX) and X-ray diffraction (XRD).The influence of microstructure on the corrosion morphologies was observed after corrosion tests in laboratory simulated atmosphere. The results indicated that magnesium-aluminum alloys with different aluminum content in the atmospheric environment had different corrosion behavior due to amount and distribution of the βphase (Mg17Al12). Mg-3Al alloy was single-phase alloy,while Mg-9Al alloy and Mg-21Al alloy were two-phase alloys. There were more βphase in Mg-21Al alloy than in Mg-9Al alloy because of its higher aluminum content. Mg-3Al alloy exhibited better atmospheric corrosion resistance than Mg-9Al alloy and Mg-21Al alloy. There were fewer corrosion products on the surfaces of Mg-3Al specimens, while severe corrosion was found to take place in both Mg-9Al alloy and Mg-21Al alloy due to the presence of the β phase in them.More specifically , it was discovered that due to the absence of the couple-actuation of βphase ,the corrosion of single -phase alloy Mg-3Al may be attributed solely to the pitting caused by high concentration of Cl- near the NaCl deposits however, with Mg-9Al alloy and Mg-21Al alloy, a more important factor for corrosion is the presence of β phase. under couple-actuation of the negative of β phase, αphase causes a corrosion along the depth extent.

Effect of different climates on anti-corrosion of acrylic/polyurethane coating have been studied in this paper. Anti-corrosion of the coatings after exposed at Wuhan and Lasa were evaluated by gross loss rate， water absorption rate， rupture strength， salt spray test and EIS. The results showed that coating exposed in Lasa aged more severely than in Wuhan， accordingly anti-corrosion of coating in Lasa lost more badly than that in Wuhan. The main way of the degradation of the coating exposed in Lasa was photo-oxidation degradation. However the way of the degradations of the coating exposed in Wuhan were photo-oxidation and hydrolytic degradation. The capability of the coating exposed in Lasa to prohibit corrosive media through coating lost more badly than that in Wuhan. The electrochemical reaction rate， which was produced on the interface， was controlled by diffusion step after the coating was exposed in Lasa for 12 months. However， the electrochemical reaction rate was controlled by electrochemical step in Wuhan.

Fluorocarbon coating is chose as the coatings researched. And this paper evaluates the results of anti-corrosion of Fluorocarbon coating exposed in different region (Wuhan and Lasa) for 3, 6, 12 months. Several experiments (measuring water absorption rate salt spray test and electrochemical behavior) are done on the coating which was exposured in Wuhan and in Lasa after different time. It is proved that although the latitude of Wuhan approaches to that of Lasa, anti-corrosion of Fluorocarbon coating is greatly affected by different climate. The coating is more severely aged in Lasa than in Wuhan. Accordingly, anti-corrosion of such coating is more badly lost in Lasa than that in Wuhan.

Low temperature melted sulfurization,catalyzed by rare earth elements,on quenched Cr12 steel surface was investigated.Morphologies and chemical compositions of the sulfide coatings were analyzed by SEM and AES,respectively.Meanwhile,atmospheric exposure test and electrolyte soaking method were applied to investigate the effect of different rare earth catalyzers and their content on corrosion resistance of sulfurized Cr12 steel.The results showed that corrosion resistance of sulfide layers in air and brine could be improved evidently due to the addition of rare earth elements in the sulfide coatings. The steady potential of sulfide coatings obviously increased and its mass-loss-rate decreased by 38%~ 50% in 5% NaCl solution.The improving extent of corrosion resistance relates with the kind and content of rare earth element.The advantage of CeCl3 was by far better than that of LaF3, CeF3 and LaCl3. Considering the excellent catalysis of LaF3, it is better to use LaF3 and CeCl3 mixture in the sulfurizing reagent,which optimized ingredient was S + 4.0 mass% LaF3 +1.0 mass% CeCl3 for the low temperature melted sulfurization of Cr12 steel.

The adsorption behavior of dodecylamine on carbon steel surface and its inhibition mechanism in HCl solutions were studied by electrochemical methods, AFM and contact angle measurements. The results showed that dodecylamine forms a monolayer film on the carbon steel surface，the inhibition mechanism is geometric blocking effect, and the contact angle increased obviously after the adsorption of dodecylamine on the carbon steel surface. It can be observed clearly from the AFM current images and AFM force-distance curves that the surface conductivity decreased obviously, and a long-range strong attractive force appeared in the surface which is covered with adsorbed dodecylamine. The functions of AFM current images and AFM force-distance curve are feasible tools for investigating the adsorption behavior of inhibitors on metal surface.

The different compositions of Cr-containing high-silicon iron-based alloys are designed which in order to study the mechanical property and the corrosive property of the alloy.the alloys are melted in mediu-frequency induction furnace.Test and research is conducted by using metalloygraphic microscope ,stereoscan and other methods.The results shows that, the mechanical property of the alloy is good when added 4%~5% Cr, at the same time the corrosion rate of the alloy in nitric acid is the lowwest.But the corrosion rate of alloy in the sulfuric acid increasing with the increasing of the percentage composition of Cr.

Three kinds of light-group sensitive materials are chosen to incorporat into primer coating, coated on the aluminum alloy surface, so as to make sure their light sensitive performance for the early prediction of corrosion of the aluminum alloy. The relation between the characteristic changes of light-group sensitive materials in coating and corrosion rate was studied. The sensitivity of light-group sensitive materials for corrosion detection was discussed. Primary connection mode between the coating and the concentration of light-group sensitive materials is set up. Finally, the mechanism of the light-group sensitive coating for detecting corrosion of the aluminum alloy is analyzed. It is found that, the three kinds of light-group sensitive materials in the coating predicted efficiently the corrosion rate of the aluminum alloy substrate.

This paper presents the joint research aimed at collecting technical information through an scientific examinations carried out on WuZhu coins from the largest mint site in the Chinese history. Optical microscopy (OM), scanning electron microscopy coupled with energy-dispersive X-ray analysis (SEM-EDX) as well as X-ray diffraction (XRD) have been used for both characterizing the elementary composition,morphology and corrosion products of coins.The analytical results revealed that the coin was made of bronze;the elementary composition is in good agreement with the information gathered through the historical survey. At the same time, the patina of coin was analyzed in this paper, mainly containing Cu2(OH)3Cl, Cu2(OH)3Cl, Cu3(CO3)2(OH)2, Cu2(OH)2CO3, CuO2 and some other minerals. The main corrosion products were azurite (2CuCO3·Cu(OH)2, blue appearance ), malachite (CuCO3·Cu(OH)2, dark green color), dioptase (CuCl2·3Cu(OH)2, CuCl2·Cu(OH)2, dark green color), cerusite (PbCO3) and others. Meanwhile, the artificial corrosion displayed that Cl-, O2, H2O were the most important factors for the erosion of WuZhu coin.

Thermal barrier coatings （TBCs） have been increasingly used to extend the durability of aircraft gas turbine engine.This not only increases components lifetime，but also allows higher engine temperatures and there－fore better efficiency.The performance valuation and analysis was reviewed to the mechanics property，oxidation resistance， hot corrosion resistance， erosion resistance， and thermal property of thermal barrier coatings.

Self-assembled monolayers (SAMs) have important application in corrosion prevention of metals due to their dense, ordered, ultrathin and stable structure. In this paper SAMs of organosulfurs, fatty acids, organosilicon derivatives, diphosphates, schiff bases and imidazolines are introduced in detail. Their applications in corrosion protection of metals, such as gold, silver, copper and iron are reviewed, respectively. The development of SAMs in the field of corrosion and protection of metals is predicted.