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This paper aims to present a correlation study on general and accelerated corrosion of the welded structure of aluminum alloy 2219 in N₂O₄.

Corrosion experiments of the Tungsten Inert Gas (TIG)-welded aluminum alloy structure were conducted under both mild and accelerated corrosion conditions by changing the water content in N₂O₄.

The experimental results indicated that both general and accelerated corrosion processes of the TIG-welded structure of aluminum alloy 2219 in N₂O₄ followed the linear equation ΔW = A + Bt, and the corrosion products were unchanged regardless of the water content in the N₂O₄ solution.

The weight loss comparison method is used to identify the structure of the conventional aluminum welding and aluminum welding structure corrosion dinitrogen tetroxide in nitric acid accelerated corrosion relationship.

This study aims to provide a theoretical basis to evaluate the suitability and integrity of corrosion pipes.

The three-dimensional models of the P110S oil pipe with local corrosion damage, general corrosion damage, pitting corrosion damage are established based on the API 579 standard using the nonlinear finite element analysis method for parametric research.

The reliability of the model is verified based on the experimental data from the existing literature. The effects of the oil pipe’s size and the corrosion damage’s type on the residual internal pressure strength are simulated and obtained. What’s more, a basic method for predicting the remaining life of corrosion damaged pipes is proposed.

The authors evaluated the residual strength of various corroded tubing, compared the tubing with different corrosion types and proposed a basic method for predicting the remaining life of the corroded tubing from the corrosion depth.

The purpose of this study is to elucidate the effect of Mn addition on the corrosion behavior of stainless steel.

Chronoamperometry, quasi-steady-state polarization and electrochemical impedance spectroscopy were used to investigate the corrosion behavior of Mn added A13Cr-HS sample and original S13Cr samples. In addition, the corrosion product film was characterized by a field emission scanning electron microscope equipped with energy-dispersive spectroscopy and X-ray photoelectron spectroscopy.

The A13Cr-HS sample with 8 wt.% Mn addition maintained good general corrosion resistance in both acidic and alkaline solutions compared to the original S13Cr sample. Additionally, the A13Cr-HS sample had good pitting resistance in an alkaline solution containing Cl⁻, but a weaker resistance in an acidic solution.

The influence of Mn addition on the formation mechanism of the passive film was systematically analyzed.

PROBABLY one of the most remarkable features of our generation has been the ability of the metallurgist to produce alloys meeting the current needs of industry in providing the requisite mechanical characteristics, capabilities of being manipulated or fashioned by established methods, and in particular instances, specific properties of resistance to erosion, corrosion, wear, impact and fatigue. Perhaps this adaptability is best exemplified in the case of light alloys, whereby scientific alloying of aluminium or magnesium bases with other elements, combined with specific thermal treatments, have imparted increased strength, durability, and, under limited conditions, resistance to corrosion, to a whole range of alloys without any appreciable sacrifice of the great advantage in initial lightness of these two base metals. In view of this, these metals, which are conveniently designated “light alloys,” have become exceedingly popular, particularly since the majority of them are eminently suitable for fabrication in the form of diecastings, which permit the reproducibility of exact forms in large quantity production. The mechanical features of light alloys, together with their capacity to be machined, or otherwise finished to shape and dimensions, are fairly widely known, but their ability and relative merits to resist various conditions of corrosive influence are not so clearly elucidated. The readers of this journal arc naturally concerned primarily with finishes of protective value rather than with those of decorative importance. In general engineering considerable confusion exists as to the behaviour of aluminium and its alloys under deleterious influences, and this tends to retard their general adoption, even though their individual mechanical properties may make them highly desirable. In some cases most unnecessarily elaborate finishes are applied for ultra precautionary purposes, while in others a complete ban is exercised rather than incur any risk. In the aircraft industry, on the other hand, the demand for minimum weight consistent with requisite strength has provided the impetus for their adoption, which in turn has led to the development of appropriate finishing methods. Even in this sphere a comparative survey of finishing methods and their efficiency covering a range of popular alloys should prove to be of interest.

This paper deals with the causes and mechanisms of internal corrosion of tanks used for the storage of crude oil and distillates. Services which are considered in this paper include crude oil storage tanks, gasoline blending and/or storage tanks and storage tanks for kerosene and heavier distillates. Fixed‐roof, as well as floating‐roof tanks, are considered. Methods for corrosion prevention and control are discussed.

To evaluate the corrosion resistance of four different stainless steels often employed in hot end exhaust components.

This paper evaluated the outcomes of the hot salt test and the cyclic oxidation test on four different stainless steels, used as hot end exhaust components. The specimens were analyzed by means of SEM for surface changes and the weight loss was considered.

The general corrosion rate and pitting resistance under all the test conditions for hot end exhaust components indicated that 434 was by far the most corrosion resistant alloy, followed by 1.4509 and 321, and lastly 304 was the least corrosion resistant. In general, the ferritic stainless steels, especially 434, outperformed the austenitic ones under all the test conditions.

The comparison of the corrosion resistance and rate, between the frequently used ferritic and austenitic stainless steels used in the exhaust system, gave a clear indication that the ferritic steels will provide prolonged service and this could be beneficial information to the manufacturers.

A new approach to summarise the materials' behaviour and their relative performance in the tests performed was developed. This proposed summary of a number of corrosion indicators could serve as a relative guide to alloy selection for use in hot end automotive exhaust systems for both manufacturers and users.

As pitting corrosion is probably the most damaging type of wet corrosion, an understanding throughout industry of this phenomenon, which is the condition between complete immunity to attack and general corrosion, is essential. This article is concerned with pitting corrosion in general, but it also contains the results of some original research recently completed by the author on the corrosion pitting of stainless steels.

Introduction Stress corrosion cracking is a phenomenon that is of interest to a wide range of metal users. When it occurs under service conditions, often without any prior indication of impeding failure, its effect may be catastrophic.

The purpose of this paper is to present a novel five‐electrode electrochemical corrosion sensor. Health degradation by the corrosion of steel in civil engineering is a persistent problem. Structural health monitoring (SHM) techniques, including embedded sensors, can greatly improve the quantification of the steel corrosion information, which can lead to promote assessments of structural safety and serviceability. To integrate the corrosion monitoring system in future, the corrosion sensor and the monitoring methods have been explored here in advance. Also, the corrosion monitoring system has been applied preliminarily in the investigation of reinforcing concrete (RC) beams.

First, a novel five‐electrode electrochemical corrosion sensor has been developed as the hardware to provide the platform for corrosion monitoring methods. Second, half‐cell potential of the RC beams has been measured before and after corrosion. Third, galvanostatic step method has been used to excite the steel‐concrete system, and the transient response of the system has been obtained and analyzed. Finally, wavelet transform algorithm has been established to analyze the electrochemical noise (EN) data of the steel bars in RC beams.

The results show that the corrosion sensor can be used effectively as the hardware to support the electrochemical measuring techniques. Much valuable information which is extracted by analyzing the potential response to the galvanostatic pulse excitation can be applied to determine the general corrosion state of the reinforcing steel. For pitting corrosion, the energy distribution plot of EN can be adopted as a benchmark method to identify the presence of the corrosion pit.

The paper provides the key techniques for a SHM system to realize corrosion monitoring of large‐scale RC structures in the future.

The purpose of this article is to help the user of chemical equipment identify and classify the different types of corrosion through actual illustrations showing the mechanical effect on the corroded parts. Theoretical discussion of the cause of the corrosive action has, in each case, been avoided unless such reference is necessary to permit better identification of the type of corrosion under discussion.