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An investigation of the behaviour of a soluble resin coating on a steel substrate was carried out by open circuit potential and electrochemical techniques. Exposure conditions were with artificial sea‐water and natural sea‐water. The anticorrosion properties of the soluble resin material and its protection of the steel panel from marine corrosion were estimated by comparison with the untreated steel. The weight effect of the film coating and the temperature of the media were also studied.

Background In the language of the steel industry, the term coated steel means, for all practical purposes, mild steel sheet or strip which is coated before it leaves the steel mill. Various coatings are employed depending upon product end use but basically they divide up into metallic coatings such as tin, zinc or aluminium; and organic coatings which are essentially paints or plastic films. Organic coatings are very often applied on top of metallic coatings, so that in the most advanced coated products there may be as many as five separate layers of material between the underlying steel and the exposed outer surface.

The purpose of this paper is to study the effect of chemical composition on the selective oxidation on the surface of bake hardenable steel, and on the surface of modified bake hardenable steel with titanium addition, annealed at different dew points.

The subject scope of the paper is the selective oxidation. The methodology used is the annealing of steels at different dew points, and the surface characterization by using atomic force microscopy, X‐ray photo electronic spectroscopy, and glow discharge optical emission spectroscopy.

The modified bake hardenable steel showed a higher oxidized area than the bake hardenable steel. The optimum condition for annealing of the bake hardenable steel was at 800°C with −30°C dp and −60°C dp as selective oxidation is less voluminous.

One suggestion for future works is the use of transmission electron microscopy for the evaluation of selective oxidation on the steel surfaces.

One practical implication is the determination of the optimum condition for annealing of the bake hardenable steel in the steel plant, decreasing the selective oxidation and increasing the quality of galvanized steels. Another implication is the discard by the steel industry of the development of the modified bake hardenable steel.

The originality of the present work is to use advanced surface analysis techniques to quantify the selective oxidation on the surface of commercial steels. The selective oxidation on the surface of steels must be minimized in order to increase the wet ability of zinc layer on the steel surface.

Use of aluminium is coming into vogue in the canning industry. However, the very much higher cost of aluminium than tin plate inhibits the scope for substitution of tin plate by aluminium. It is therefore of interest to examine whether steel coated with aluminium by any of the known methods is suitable for manufacture of containers for canned products. Aluminium‐coated steel can be considered only if the coating has a more negative potential than the base metal. In a study of the behaviour of sprayed aluminium coatings on mild steel in sodium chloride solutions at different pHs, Ross has pointed out that sprayed aluminium (99.5%) is more negative than steel in neutral and alkaline solutions. In this paper, the potential relationships between steel, steel sprayed with aluminium, and aluminised steel in some organic acids commonly present in food stuffs are discussed.

Babbitt bush is easy to cause severe adhesive wear due to unexpected journal fall. This paper aims to improve wear resistance of Babbitt bush.

A soft/hard hybrid surface mircoprofile of Babbitt alloy/steel was fabricated by a technology of laser texture combined with hot-pressing. The friction and wear performances of bare steel (steel-h), Babbitt bush on steel (steel-s) and Babbitt filled in dimples of steel (steel-hs) were conducted on a ball-on-disc tester under dry and lubricated conditions.

The results showed that wettability of steel-hs was enhanced by forming soft/hard hybrid surface. Compared with steel-s, the stability of friction coefficient curve of steel-hs was improved without increasing coefficient friction. The wear resistance of steel-hs was remarkably enhanced under dry and lubricated conditions.

The originality of this paper is as following: to improve the tribological properties and to prolong service life of steel-s, soft/hard hybrid surface of Babbitt filled in dimples of steel substrate was successfully fabricated by laser texturing combined with hot-pressing. This paper showed that the lipophilicity of steel-hs was best among those of steel-s and steel-h. Babbitt alloy as a soft filler on dimples of steel substrate improved anti-wear of steel-s remarkably. It provides a new way to fabricate Babbitt as bushing on steel substrate.

This study aims to analyze the dynamic monitoring of deformation damage of steel structure buildings in long-term use. Although the steel structure building has the advantage of high structural strength, it will be deformed after being affected by factors such as corrosion and impact during long-term use, and which will affect building safety, especially the public building facilities. The dynamic monitoring of its security is an indispensable means.

This paper briefly introduced the principle of building information modeling (BIM)-based steel structure building information monitoring and the dynamic information monitoring system based on this principle. Then the monitoring system was used to analyze an operational steel structure suspension bridge in Xinxiang City, Henan Province, China, and compared it with the monitoring system based on back propagation (BP) neural network.

The results showed that the fitting degree of the dynamic deformation displacement data processed by BIM-based monitoring system was higher than that processed by BP-based monitoring system. Based on the comprehensive comparison of the dynamic data of all monitoring points, the BIM-based monitoring system had higher accuracy of deformation displacement monitoring and reliability of structural safety evaluation.

In summary, the BIM-based steel structure building monitoring system can effectively monitor the dynamic information of steel structure information.

This study aims to report the CO₂ corrosion performance of 3Cr steel and 3Cr2Al steel and reveal the role of aluminum in mitigating corrosion of low-Cr steel.

Aluminum was added to 3Cr steel to prepare a new type of 3Cr2Al steel, and the effect of aluminum on the corrosion resistance of pipeline steel was studied using morphology observation and composition analysis, weight loss tests and electrochemical test.

In the CO₂/O₂ coexistence environment, the average corrosion rate of the 3Cr2Al steel was obviously lower than that of the 3Cr steel. The addition of aluminum expanded the range of prepassivation, and the dynamic potential polarization curve of 3Cr2Al steel showed duplex prepassivation phenomena. 3Cr steel underwent severe local corrosion, and 3Cr2Al steel underwent uniform corrosion. The addition of aluminum contributed to the formation of a dense corrosion product layer and greatly reduced the localized corrosion sensitivity.

The studies on CO₂ corrosion of aluminum containing low-Cr steel are quite rare. This study clarifies the role of aluminum by comparing the corrosion behavior of 3Cr2Al and 3Cr steel. The effect of aluminum on the growth of corrosion product film was discussed, and the duplex prepassivation phenomena of Cr and Al were revealed.

The phosphatability of a steel surface and, hence, the corrosion protection achieved is related to the quality of that steel surface. It is the intent of this paper to determine what parameters of the steel surface influence phosphatability. This was done by examining the influence of steel surface roughness and contamination on zinc phosphate coating quality, and by determining the relationship of phosphate coating weight and density to the corrosion resistance of painted steel. A high correlation was found between the amount of corrosion creepback of phosphatized and painted steel substrates and the amount of organic carbon present on the surface of the steel. The carbon, analyzed by Auger Electron Spectroscopy, average approximately 50A in depth and is not removed by phosphate precleaning operations. The carbon inhibits the formation and development of phosphate coatings which are required to provide satisfactory corrosion resistance.

The purpose of this study was to determine correlation between an accelerated cyclic corrosion test (S6‐cycle test) specified in Japanese Industrial Standards K5621 and field exposure tests, and to open up applications of the accelerated tests in various regional environments.

The S6‐cycle corrosion test was carried out on structural steels for 30, 60, 90, 120 and 150 days and metal coating films for 100, 200 and 300 days. Comparing the weight loss of the steels with 1‐, 3‐, 5‐ and 9‐year field exposure test data at 31 sites in Japan. Correlation of the S6‐cycle tests to the field exposure tests was determined by acceleration coefficients.

The correlation between the S6‐cycle test and the field test on uncoated structural steels can be determined by acceleration coefficients based on flying salt amount. The coefficients were applicable for durability prediction of uncoated, zinc hot‐dip galvanized and painted steels.

In determination of the accelerated coefficients, only the flying salt amount was considered. Others factors such as temperature and humidity will be considered in future work.

Using the S6‐cycle corrosion test and its accelerated coefficients, the thickness loss of uncoated structural steels and zinc hot‐dip galvanizing is predictable in a short time. Corrosion degradation of coated steels is also predictable approximately.

This paper contributes to open up the application of accelerated cyclic corrosion test to evaluating corrosion resistance of steel bridge members.

Duplex stainless steels have become important competitors to austenitic stainless steels in many applications and a great deal of attention has focused on the welding aspects. The introduction of modern grades with improved properties and a competitive price level have increased their use in the offshore, petrochemical and shipbuilding industries, for example. In particular the newer grades, with their higher nitrogen content and improved weldability, have moved duplex stainless steels from a position as “interesting” materials to one of “useful in practice”. However, duplex stainless steels differ from austenitic grades in some respects, and know‐how combined with the use of appropriate welding procedures and consumables is therefore the key to successful welding.