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Corrosion Behavior of Metal, Alloy, and Composite
Published in Suneev Anil Bansal, Virat Khanna, Pallav Gupta, Metal Matrix Composites, 2023
There are distinct types of metallic corrosion such as pitting corrosion, uniform corrosion, inters granular corrosion, galvanic corrosion, stress corrosion cracking, erosion corrosion, etc. The distinct types of corrosion types and their testing methods are represented in Figure 3.14.
Surface Failure
Published in Ansel C. Ugural, Mechanical Engineering Design, 2022
Corrosion is the deterioration or destruction of a material because of a chemical reaction with its environment. It is the wearing away of metals owing to chemical reaction. Usually, this means electrochemical oxidation of metals in reaction with an oxidant such as oxygen. Rusting is the term commonly used for the oxidation of iron and steel. It represents the formation of an oxide of iron due to oxidation of the iron atoms in solid solution. This kind of damage often produces oxide(s) and/or salt(s) of the original metal. The main culprits in corroding metals are hydrogen and oxygen. Pure metals are customarily more resistive to corrosion than those containing impurities or small amounts of other elements.
Biopolymer Composites and Nanocomposites for Corrosion Protection of Industrial Metal Substrates
Published in Hatem M.A. Amin, Ahmed Galal, Corrosion Protection of Metals and Alloys Using Graphene and Biopolymer Based Nanocomposites, 2021
Saviour A. Umoren, Moses M. Solomon
Corrosion, commonly defined as the deterioration of a material (usually a metal) or its properties because of a reaction with its environment, is a global problem. NACE International, The Corrosion Society, estimates that global corrosion and its consequences cost developed nations about 3–5% of GDP or GNP [1]. Methods commonly employed to combat corrosion include cathodic protection, materials selection, coatings and linings and corrosion inhibitors. Corrosion inhibitors form a layer over the metallic substrate and protect the metal from corrosion, thereby enhancing the life of the metal. Coatings designed for corrosion protection must offer an effective physical barrier, impeding the access of aggressive species to the metallic interface. For many years, the most effective corrosion protection systems were based on the use of chromate-rich surface treatments and/or primers and pigments based on chromates [2]. However, the current legislation imposed by REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) prohibits the use of hexavalent chromium in almost all sectors except the aerospace industry [3]. Many alternatives have been explored so far, including a wide range of “green” surface treatments and pretreatments, environmentally safe pigments and natural corrosion inhibitors [4]. The latest developments propose coatings with low volatile organic compounds (VOCs), based on waterborne formulations and isocyanate-free compositions, as well as smart and self-healing polymers [4].
Effect of low calcination temperature on the corrosion inhibition performance of biomass based Na2SiO3 on mild steel immersed in tap water
Published in Cogent Engineering, 2023
Addis Lemessa Jembere, Melkamu Birlie Genet
Corrosion is the spontaneous and irreversible deterioration of metals and alloys by chemical or electrochemical reactions in the presence of moisture in their environment. It is a natural situation and it has a huge outcome on maintenance and repair costs in the industry (Anaee, 2014; Karekar et al., 2018; Pramudita et al., 2019). It is very difficult to eliminate completely on the metal surfaces and it is considered one of the major industrial problems, mainly in the systems involving water such as cooling systems, heating systems (boilers), steel pipelines, etc. (Asra et al., 2017; Awizar et al., 2013; Govardhane & Shende, 2021). A study by the National Association of Corrosion Engineers (NACE) conducted in 2016 G.C. estimated that the global cost of corrosion to be $ 2.5 trillion annually, equivalent to about 3.4% of the global Gross Domestic Product (GDP; Hou et al., 2017; Skovhus et al., 2017). However, the cost can be reduced enormously in the range of $375-875 billion annually by applying highly efficient corrosion inhibiting technologies (Koch, 2017; Tang, 2019; Xavier Stango & Vijayalakshmi, 2018). Due to the high costs and problems associated with corrosion-resistant materials, the use of corrosion inhibitors is a realistic and cost-effective alternative that can be designed.
Effect of Nb Addition on Corrosion Resistance of U-6Zr Alloys
Published in Nuclear Technology, 2023
Masrukan Masrukan, M. Husna Alhasa, Maman Kartaman, Juan Carlos Sihotang
Corrosion is the process of material degradation/destruction caused by the influence of the surrounding environment. This situation is the natural tendency of a material to return to its most stable state. In most metallic materials, this condition is caused by the formation of oxides or sulfides, or basic metal compounds that are generally considered metal ores.[5] The corrosion rate (CR) is influenced by several factors, including the concentration of the oxidizing agent, the flow rate of the corrosive fluid, temperature, and degree of acidity.[6–8] The concentration of dissolved oxygen in a solution can significantly impact the measured CRs of a metal. When a metal is exposed to an oxygen-containing environment, such as water, a reaction occurs on the metal’s surface, leading to corrosion. The presence of dissolved oxygen in the solution can accelerate this reaction, resulting in increased CRs.[9] As a result, the measured CRs are likely to be higher if the solution contains dissolved oxygen than if it is deaerated or if the dissolved oxygen concentration is controlled. In this research, we measured the CRs of the metal using the same solutions without deaerating them.
EUROCORR 2019: ‘New times, new materials, new corrosion challenges’: part 2
Published in Corrosion Engineering, Science and Technology, 2020
‘Investigations of corrosion due to calcium leaching’ were described by Y. Schiegg (TFB AG, Switzerland). If cement-based materials are in contact with liquids of lower ion concentration, the chemical potential gradient induces ionic diffusion, e.g. Ca2+, from the pore solution towards the solvent (typically water). This increases the porosity and enhances the ingress of corrosion promoting substances. Leaching investigations and electrochemical measurements give similar initiation times for ordinary Portland cement (OPC) and for OPC blended with fly ash (FA) and limestone (LS). For OPC blended with high amounts of blast furnace slag, de-passivation takes about twice as long compared with that found by electrochemical measurements. Finally, it was shown that the time for corrosion initiation increases with CaO content.