The oxidation behavior of Fe,Cr and Ni in SUS304 stainless steel implated with 3 keV O2+ ions has been investigated by in situ synchrotron rasiation X-ray photonelectron spectrocsopy(SR-XPS).For comparision,the same experiments were carried out for the pure Fe, Cr and Ni metals.The oxide films of stainless steel and oure metals have also been observed by scanning tunneling microscope (STM).It was found that the oxidized species of Cr and Ni in SUS304 changed from FeO to Fe2O3 with the increase of the doses of O2+.The oxidation rates of Fe and Cr in SUS304 were faster than those in respective pure metals,while the oxidation rate of Ni in sus304 was lower than thatin pure Ni.NiO layer was not formed on SUS304 until Fe2O3 appeared, which suggests that Fe2O3 has a special effect on the basis of the results of STM and SR-XPS.

The implantation behavior of O+ in SUS304 satinless steel,pure Fe,Ni and Cr has been studied by SR-XPS in situ.All of O+ ion has combined with the metal atoms in SUS304, on the other hand, only oart of O+ ion reacted with metal atoms in pure Fe, Ni and Cr.Oxygen existed in two chemical states in pure Fe,Ni,Cr: "reacted oxygen" which combined with metal element and "dissolved oxygen"which just insert into the crystal lattice.The ratio of "dissolved oxygen"is decided by the chemical reactivity the oure metal has.

Current distributions in a cathodically protected crevice between a simulated coating and segmented mild steel electrodes were measured in diluted NaCl solutions.The effects of the control potential,Solution conductivity and crevice thickness on the current distribution were studied.The results showed that the xurrent distribution inside the crevice became uniform with prolonging of polarization time.In general, the more negative the control potential, the greater the solution conductivity and crevice thickness,the larger the current density inside the crevice.

The corrosion of pure in the CO2 solution with NaCl is a kind of localized corrosion in-situ observed by scanning tunnel microscope (STM).The addition of imidazoline amide(IM) in the CO2 solution.inhibited thes kind of corrosion, which showed the adsorption of IM on the surface of pure iron is very stable.When the potential applied on the pure iron is over the adsorption potential, IM will desorb from the surface of iron,which is studied by the microcosmic and macrocosmic methods.

Anodic polarization curves of carbon steel were measured using rotating disk electrode. The inhibition mechanism of carbon steel with tungstate in deaerated neutral solution was investigated. The results indicated that the passivation film formed on the surface of carbon steel during the process of anodic polarization. The existence of Mg2+ ions in solution could effected the formation of passivation film.

Repassivation behavior behavior of 316Lstainless steel in fretting has been studied in different NaCl solutions.And the effect of crevice corrosion occurring during fretting process had been discussed.The results showed that different solutions resulted in different repassivation behavior.But the difference of repassivation behaviors in different solutions ras not remarkable:in pH10.0(0.9% NaCl)solution,repassivating process could last for about 5×10 4 cycles;while fretting in other corrosive solutions,no more repassivation process took place after 4×10 4 cycles.When fretting was carried out in deionized water the material had better repassivation ability. The growing film might take up 17 percent of passive film in static condition.The evidence suggested that passive film could not protect the material from corrosion damage effectively in fretting

The rule of a long term, several interval seawater corrosion data of 90;10 Cu/Ni alloy (CDA706)tube and plate has been studied.Reaults showed that the alloy tube with relatively low tensile strength suffered severe corrosion in seawater of Xiamen and Zhoushan,exhibiting morphology of erosion and intergranular corrosion.But the alloy plate with relatively high tensile strength possessed bigger temperature sensitivity i.e. the corrosion rate was higher in Yulin than Yulin because of the higher seawater temperature.The detail of corrosion morphology and corrosion product film were observed and analyzed by using advanced metal physics methods of coloring metallographu (CM),scanning electron microscopy (SEM),electron dispersive of X-ray analysis(EDXA) etc.to find out the reasons of different sensitivities occurring on these alloy materials.It was found that corrosion sensitivities of the two kind materials were due to the grain boundary defects produced when the materials were processed.

Chemometrics is one of effective methods for cluster analysis of complicated system.In this paper,fuzzy cluster analysis constructed by numeric genetic algorithm was developed to study and evaluate the electrochemical inhomogeneity of rust preventing oil film. It was pointed out that rust preventing oil film had three types of film, protective film and unstable film It is suggested that it ciuld make fast evaluation of rust preventing oil film using this method, and the results were also sastisfied.

New processes of dehydration with triglycol are applied in the transport of natural gas in Sichuan-east Datianchi oil/gas field.Accidents of cracking and perforation still occurred in the collection pipe of natural gas transport. The spot loss-sample and corrosion product collected form the pipe were analzed with X-ray diffraction, electron probe microscopy analysis (EPMA),scanning electron microscope and thermal analysis. The analysis results show that the collection pipe of natural gas transport suffered severe hydrogen sulfide corrosion though new processes of dehydration had been introduced. The pattern of corrosion showed fron loss-sample was pitting corrosion. The composed of FeS, FeS2, Fe3S4,and Fe9S8, some ferrous oxide composition and something else.Thermal analysis of corrosion product sample shows that a strong exothernic reaction exists between 170℃ to 350℃, the enthalpy value(△H) is about -256.8J/g.