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Three types of alloys have been chosen, and subjected to three different varieties of macro‐strains, e.g. corrosion‐pittings in a high strength low‐alloy, sensitization‐induced precipitation in an unstabilized 304 s.s. and cold‐working stresses in FeNiMoB and FeNiMoBSi metallic glass foils for diagnostic studies in corrosion console. Attempts to correlate the galvanic activity of these substrates with the imposed galvanic micro‐strains using an entirely new type of criterion, namely the distance between the forward and backward‐scan, indicated by “d” value in terms of current at a particular chosen potential. This technique, however, is limited by a threshold extent of surface‐strains, in terms of either anodic or cathodic stress concentration‐points above which the surface either develops an anodically activated film or it starts behaving as an effective cathode. The galvanic interactions of the surface, under such conditions, become minimal so that the “d” values no longer remain an increasing function of the increasing surface galvanic strain.

Stainless-clad bimetallic steels (SCBS) are widely investigated in some extremely environmental applications areas, such as polar sailing area and tropical oil and gas platforms areas, because of their excellent anticorrosion performance and relatively lower production costs. However, the properties of SCBS, including the mechanical strength, weldability and the anticorrosion behavior, have a direct relation with the manufacturing process and can affect their practical applications. This paper aims to review the application and the properties requirements of SCBS in marine environments to promote the application of this new material in more fields.

In this paper, the manufacturing process, welding and corrosion-resistant properties of SCBS were introduced systematically by reviewing the related literatures, and some results of the authors’ research group were also introduced briefly.

Different preparation methods, such as rolling composite, casting rolling composite, explosive composite, laser cladding and plasma arc cladding, as well as the process parameters, including the vacuum degree, rolling temperature, rolling reduction ratio, volume ratios of liquid to solid, explosive ratio and the heat treatment, influenced a lot on the properties of the SCBS through changing the interface microstructures. Otherwise, the variations in rolling temperature, pass, reduction and the grain size of clad steel also brought the dissimilarities of the mechanical properties, microhardness, bonding strength and toughness. Another two new processes, clad teeming method and interlayer explosive welding, deserve more attention because of their excellent microstructure control ability. The superior corrosion resistance of SCBS can alleviate the corrosion problem in the marine environment and prolong the service life of the equipment, but the phenomenon of galvanic corrosion should be noted as much as possible. The high dilution rate, welding process specifications and heat treatment can weaken the intergranular corrosion resistance in the weld area.

This paper summarizes the application of SCBS in marine environments and provides an overview and reference for the research of stainless-clad bimetallic steel.

The high specific strength makes magnesium alloys have a wide range of applications in aerospace, military, automotive, marine and construction industries. However, its poor corrosion resistance and weldability have limited its development and application. Friction stir welding (FSW) can effectively avoid the defects of fusion welding. However, the microstructure, mechanical properties and corrosion behavior of FSW joints in magnesium alloys vary among different regions. The purpose of this paper is to review the corrosion of magnesium alloy FSW joints, and to summarize the protection technology of welded joints.

The corrosion of magnesium alloy FSW joints includes electrochemical corrosion and stress corrosion. This paper summarizes corrosion protection techniques for magnesium alloys FSW joints, focusing on composition, microstructure changes and surface treatment methods.

Currently, this research is mainly focused on enhancing the corrosion resistance of magnesium alloy FSW joints by changing compositions, structural modifications and surface coating technologies. Refinement of the grains can be achieved by adjusting welding process parameters, which in turn minimizes the effects of the second phase on the alloy’s corrosion resistance.

This paper presents a comprehensive review on the corrosion and protection of magnesium alloys FSW joints, covering the latest research advancements and practical applications. It aims to equip researchers with a better insight into the field and inspire new studies on this topic.

A film called ‘Corrosion in Action,’ made by The International Nickel Co. Inc., American associates of The Mond Nickel Co. Ltd., stresses the need for understanding and controlling corrosion. The film is in three parts and runs for just over an hour. By example and analogy, involving the use of animated diagrams as well as photography, it is able to drive its points home in a way that a mere written explanation, however good, cannot. However, a brief summary of the main points discussed, in combination with some of the actual shots from the film, may recapture some of the film's force and clarity and help to spread knowledge of basic corrosion principles.

Much misunderstanding exists about the relationship between tables of normal electrode potentials and the galvanic series of the metals on the one hand, and the possibilities of galvanic or bimetallic corrosion on the other. It is too often assumed that a direct relationship exists and that the corrosion behaviour of a pair of metals can be predicted from the potential difference between them. This article briefly evaluates the position.

Important reserves of oil and gas, which are left to be discovered and produced, are mainly concentrated in challenging locations and under severe conditions such as high pressure (HP)/high temperature (HT). The presence of aggressive environments including H₂S, CO₂ and chlorides plus HP/HT causes a series of corrosion problems, which cost the oil industry billions of dollars a year. Thus, there is an increasing challenge for tubes (i.e. oil country tubular goods, for short, OCTG) used in producing oil and gas. The purpose of this study is to summarize different kinds of corrosion problems and their mitigation, to more efficiently protect OCTG from corrosion.

To effectively select proper mitigation methods, the mechanism of corrosion must be understood, which can be classified into four categories: sweet corrosion, sour corrosion, galvanic corrosion and microbiologically induced corrosion. Also, the effects of environmental and material factors on the corrosion rate are presented. Subsequently, current technology of mitigating these corrosion problems has been discussed, including the development of materials, application of chemical inhibitors and application of protective layers.

It is stressed that limits exist for each individual mitigation method; therefore, a careful balance between economic life of OCTG and safety in operation is required.

The main purpose of this essay is to give a brief review and detailed introduction and analysis about those technologies.

Studere Corrosion has been described as a transformation process in which a metal passes from its elementary form to a combined condition. It includes wet and dry corrosion; the former requires an aqueous environment and the latter is oxidation. Deterioration of the metal due to physical causes is not called corrosion, but is known as erosion, galling, wear, etc, depending upon the material and the conditions. Corrosion is the result of the metal chemical or an electrochemical reaction with its environment. Sometimes the chemical reaction is accompanied by physical deterioration, as in fretting corrosion. It should be noted here that the term corrosion is only applied to metals; non‐metals rot, crack or erode. Also it should be appreciated that only ferrous metals can ‘rust’, i.e. form hydrous ferric oxides.

Under severely aggressive conditions, such as those experienced in the chemical industry, there has been extensive use of stainless steels in order to reduce corrosion losses. The successful industrial use of stainless steels led to requests for information on the corrosion resistance of stainless steels and similar alloys in sea‐water. This paper was awarded a prize in the Essay competition organised by the Corrosion Group of the Society of Chemical Industry, 1959.