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The purpose of this paper is to develop new types of anchor bolt materials by adding corrosion-resistant elements for alloying and microstructure regulation.

Three new anchor bolt materials were designed around the 1Ni system. The stress corrosion cracking resistance of the new materials was characterized by microstructure observation, electrochemical testing and slow strain rate tensile testing.

The strength of the new anchor bolt materials has been improved, and the stress corrosion sensitivity has been reduced. The addition of Nb makes the material exhibit excellent stress corrosion resistance under –1,200 mV conditions, but the expected results were not achieved when Nb and Sb were coupled.

The new anchor bolt materials designed around 1Ni have excellent stress corrosion resistance, which is the development direction of future materials. Nb allows the material to retain its ability to extend in hydrogen-evolution environments.

This study aims to study the effect of Sn on the corrosion behavior of weathering steel (WS) in a simulated tropical marine atmosphere.

Indoor alternate immersion tests, electrochemical measurements and real-time current-monitoring technology based on the galvanic corrosion principle were used and the scanning electron microscope, X-ray diffraction, X-ray photoelectron spectroscopy and electron probe microanalyzer were used to analyze the morphology and component of the rust layer.

The results indicated that Sn has a positive influence on the corrosion process. Sn participated in the composition of the rust layer in the form of SnO₂ and is enriched in the inner rust layer. SnO₂ participated in the coprecipitation process with iron oxides and oxyhydroxides, which promoted further transformation of γ-FeOOH to α-FeOOH. As a result, the rust layer of Sn-containing steel was continuous, compact and effectively blocked the invasion of aggressive Cl⁻. Therefore, the additive of Sn enhanced the corrosion resistance of WS in a simulated tropical marine atmosphere.

The corrosion behaviors of WS were researched by the real-time current-monitoring technology which was rarely used.

This study aims to construct a double layer heat insulation coating based on hollow glass microspheres (HGMs) and to investigate the effect of particle size on barrier property and heat insulation performance.

The waterborne double layer coating was composed of an anticorrosive epoxy ester primer and an HGM-containing silicone acrylic topcoat. With varied HGM sizes (20 μm, 40 μm, 60 μm and a 1:3 w/w mixture of 20 and 60 μm particles), the coating was immersed in 3.5 wt% NaCl solution for 28 days and was then subjected to a salt spray test for 450 h. The barrier properties of the coating were evaluated through electrochemical impedance spectroscopy. Heat insulation performance was examined using a self-made device.

The addition of HGMs decreased the barrier properties of the coating by creating particle/resin interfaces for water penetration. In the HGMs-containing coatings, the use of larger HGMs showed relatively good barrier properties because of the lower particle density. The coating with smaller particles yielded a higher heat insulating capacity as indicated by lower equilibrium temperatures.

Future work will be focused on improving the barrier properties of the coating. Field exposure tests should also be performed to assess the long-term performance of the coating.

The mechanical properties of the coatings in this study also implied that HGMs can be used to develop scratch-resistant and impact-resistant coatings. Other potential applications for further studies include the uses of HGMs for coatings with improved fire retardancy and electromagnetic interference shielding.

A double layer coating was developed to provide balanced performance on both anticorrosion and heat insulation. The effects of HGM size were particularly highlighted.

The purpose of this paper is to determine the failure reasons and failure mechanism of the commercially pure titanium air conditioning condenser.

In this paper, chemical analysis, metallographic observation, visual examination and scanning electron microscope examination, corrosion products analysis and working conditions analysis were adopted for determining the reasons for the failure of the condenser.

The results indicated that TA2 titanium pipe perforation failure is caused by the synergistic effect of crevice corrosion and deposit corrosion. The corrosion processes can be divided into three steps.

This research is an originality study on the failure case of a commercially pure titanium air conditioning condenser. This study makes up for the shortage of titanium alloy failure cases and also gives the result of the failure reason and failure mechanism for titanium, which has an engineering significance.

The purpose of this paper was to study the relationship between safe storage life and storage mode of hot-rolled sheet (Q235, X70) in humid environment, and a prediction model of safe storage life under different storage modes was established.

The corrosion behavior of hot-rolled sheets under different storage conditions was studied with immersion experiment and morphology observation.

The results show that pitting occurs on the hot-rolled sheets in humid environment, and the corrosion behavior is strongly related with the storage mode. When they are stored separately, the number and depth of pits first increase and then decrease as the Cl⁻ concentration rises, while for the stack storage, pit depth increases with increasing Cl⁻ concentration. The safe storage time of separate storage is longer than that of stack storage. Based on this, a model of chloride ion concentration and storage life was established.

A storage safe life model of hot-rolled sheet in humid environment is proposed.

This paper aims to analyze a failure case of a P110 tube in a CO₂ flooding well.

The chemical composition, microstructure and mechanical properties of the failed P110 tubing steel were tested, and met the API Spec 5CT standard. The fractures were investigated by scanning electron microscopy and energy dispersive spectroscopy.

Fracture was induced by stress corrosion cracking (SCC) and that the stress concentration caused by the mechanical damage played an important role in the failure. The failure case is a SCC failure affected by mechanical damage and galvanic corrosion.

The effect of the infiltration of groundwater was studied in the failure case. The stress concentration caused by the mechanical damage played an important role in the failure.

This study aims to develops a new-type low-alloy corrosion resistant steel containing Sb and investigate the corrosion mechanism of this new-type low-alloy steel.

Energy dispersive spectrometer, X-ray photoelectron spectroscopy, X-Ray diffraction and scanning electron microscopy were used to evaluate the corrosion resistance of the rust layers formed on these samples. Laser confocal microscopy was used to observe the corroded surfaces of the steels.

Results showed that Sb added can consume H⁺ in the solution, thereby preventing the oxygen reaction to slow down the corrosion rate. Meanwhile, a stable and insoluble substance (Sb₂O₃) in the acidic solution would be produced when the reaction of the product of Sb and H⁺ with the enough dissolved oxygen in the solution. Due to the precipitation of Sb₂O₃ and iron oxyhydroxides, the rust layer of Sb-containing steel became more uniform and compact, which resulted in better corrosion resistance in acid environment.

In this study, a new-type acid resistant low-alloy steel containing Sb was developed. Compared with the results, the corrosion mechanism of the new-type low-alloy steel in acid environment was discussed.

This study aims to achieve long-term prediction on a specific monotonic data series of atmospheric corrosion rate vs time.

This paper presents a new method, used to the collected corrosion data of carbon steel provided by the China Gateway to Corrosion and Protection, that combines non-linear gray Bernoulli model (NGBM(1,1) with genetic algorithm to attain the purpose of this study.

Results of the experiments showed that the present study’s method is more accurate than other algorithms. In particular, the mean absolute percentage error (MAPE) and the root mean square error (RMSE) of the proposed method in data sets are 9.15 per cent and 1.23 µm/a, respectively. Furthermore, this study illustrates that model parameter can be used to evaluate the similarity of curve tendency between two carbon steel data sets.

Corrosion data are part of a typical small-sample data set, and these also belong to a gray system because corrosion has a clear outcome and an uncertainly occurrence mechanism. In this work, a new gray forecast model was proposed to achieve the goal of long-term prediction of carbon steel in China.

This paper aims to investigate the effect of cerium modification and electrodeposition on the properties of the silane films obtained. Besides, the influence of dissolved oxygen was also researched through inhalation of oxygen or nitrogen. Moreover, the corresponding corrosion behavior of the silane films was also studied.

In this paper, surface morphology and corrosion-resistant properties of the films were characterized by scanning electron microscopy, electrochemical impedance spectroscopy, immersion test and the salt spray test.

The paper reveals that all the practical parameters including the concentration of dissolved oxygen had a marked effect on the anti-corrosive performance of the films, which may be attributed to the dense and compact structure of the films obtained. Furthermore, the self-healing ability of the films had also been enhanced through the rise of dissolved oxygen concentration in proper proportion.

This paper reveals the effect of practical parameters on the properties of the silane films obtained and the corrosion behavior of these films.

The purpose of this paper is to understand the process of failure of scale and the corrosion resistance of scale to the substrate in an atmospheric environment.

The corrosion behaviour of X65 pipeline steel with different types of oxide scale was analysed using the natural environment exposure corrosion test, scanning electron microscopy analysis, electrochemical corrosion polarization curve test and other methods in a warehouse environment.

The results of this research show that one type of oxide scale, which is rough, has an uneven microstructure, and exhibits weak adhesion to the matrix, does not protect the substrate from corrosion. Conversely, the uniform, dense oxide scale, which exhibits strong adhesion to the matrix, provides effective protection to the steel. However, as the corrosion develops, the corrosion rate of the substrate tends to accelerate, especially when the structure of the oxide scale is damaged to a certain extent.

The corrosion mechanism of the oxide scale on hot rolled steel in an atmospheric environment has been proposed.