Corrosion represents one of the most serious noticed in the industrial world especially in petrochemical, petroleum, power plants, etc.
Billions of Dollars are lost yearly due to the affect of corrosion in the world.
General Corrosion
Galvanic Corrosion
Concentration-Cell Corrosion
Intergranular Corrosion
Stress Corrosion Cracking
Pitting
IRJET-Review of Marine Environmental Corrosion and Application of an Anti-Cor...IRJET Journal
This document discusses corrosion of ship hulls and methods to prevent corrosion through protective coatings. It provides background on corrosion processes and types, including uniform corrosion and localized corrosion like pitting and crevice corrosion. Different zones of a ship are discussed in relation to corrosion risk and appropriate paint types. Various international standards for marine paints are also outlined. The conclusion emphasizes the importance of using a primer coat and high-quality filler and paint, as well as the potential for sampling inspection plans to improve coating quality and monitoring on ship hulls.
IRJET- Corrosion Analysis by Acid Concentration in Oil and Gas PipelinesIRJET Journal
This document discusses corrosion in oil and gas pipelines. It identifies some key causes of corrosion as acid concentration, temperature, and presence of water and chemicals like CO2 and H2S. Internal corrosion is a major problem and can occur due to water, sediments, CO2, and H2S accumulating on the inner pipe surface. Corrosion causes damage through metal loss, weakening of pipe integrity, and environmental damage from oil spills. Proper material selection and corrosion protection methods are needed to control corrosion in pipelines and reduce economic and safety impacts.
Corrosion inhibitors are chemical substances that minimize or prevent corrosion when added in small concentrations to an environment. They work by forming protective films on metal surfaces or reacting with corrosive components. Inhibitors can be inorganic, like chromates and nitrites, or organic compounds. They are applied through continuous injection, batch treatment, or squeeze treatment. The efficiency of an inhibitor depends on its concentration and ability to form protective barrier films on metals. Scavengers like hydrazine and sodium sulfite are also used to remove oxygen which promotes corrosion. Inhibitors find applications in various industries like petroleum, packaging, sour gas, and cooling systems.
Cathodic protection and chemical inhibitors are two widely used methods to combat corrosion in New Zealand. Cathodic protection works by forcing the metal's potential into a negative region where it is stable, using either a sacrificial anode or external power supply. Chemical inhibitors remove electrons from the metal's surface, pushing its potential into a positive region where a protective oxide film forms. Both methods control the metal's surface charge to reduce corrosion.
Corrosion is the deterioration of metals due to chemical reactions with the environment. It can have serious consequences like structural failure, contamination, and equipment damage. Corrosion occurs via electrochemical reactions where the metal oxidizes (anode) and other reactions reduce (cathode). Factors like galvanic effects, stress, and aggressive ions can accelerate corrosion. Common methods to control corrosion include using coatings, alloying, removing oxygen, adding inhibitors, and electrochemical protection like cathodic protection. Proper prevention strategies can significantly extend the lifetime of metal structures and equipment.
Power plant chemistry corrosion theory and its preventionumar farooq
The document provides information about corrosion theory and prevention in power plants. It defines corrosion and discusses corrosion mechanisms such as the corrosion cell and various corrosion reactions. It also covers different types of corrosion like general corrosion, pitting, galvanic corrosion and stress corrosion cracking. Additionally, it lists factors that affect corrosion rates like dissolved gases, solids, temperature and acidity. Finally, it discusses methods of corrosion control like using corrosion inhibitors and promoting protective scales to change the corrosive environment. The document is a technical report on corrosion prepared by Umar Farooq, a chemist at SEC in Saudi Arabia.
IRJET-Review of Marine Environmental Corrosion and Application of an Anti-Cor...IRJET Journal
This document discusses corrosion of ship hulls and methods to prevent corrosion through protective coatings. It provides background on corrosion processes and types, including uniform corrosion and localized corrosion like pitting and crevice corrosion. Different zones of a ship are discussed in relation to corrosion risk and appropriate paint types. Various international standards for marine paints are also outlined. The conclusion emphasizes the importance of using a primer coat and high-quality filler and paint, as well as the potential for sampling inspection plans to improve coating quality and monitoring on ship hulls.
IRJET- Corrosion Analysis by Acid Concentration in Oil and Gas PipelinesIRJET Journal
This document discusses corrosion in oil and gas pipelines. It identifies some key causes of corrosion as acid concentration, temperature, and presence of water and chemicals like CO2 and H2S. Internal corrosion is a major problem and can occur due to water, sediments, CO2, and H2S accumulating on the inner pipe surface. Corrosion causes damage through metal loss, weakening of pipe integrity, and environmental damage from oil spills. Proper material selection and corrosion protection methods are needed to control corrosion in pipelines and reduce economic and safety impacts.
Corrosion inhibitors are chemical substances that minimize or prevent corrosion when added in small concentrations to an environment. They work by forming protective films on metal surfaces or reacting with corrosive components. Inhibitors can be inorganic, like chromates and nitrites, or organic compounds. They are applied through continuous injection, batch treatment, or squeeze treatment. The efficiency of an inhibitor depends on its concentration and ability to form protective barrier films on metals. Scavengers like hydrazine and sodium sulfite are also used to remove oxygen which promotes corrosion. Inhibitors find applications in various industries like petroleum, packaging, sour gas, and cooling systems.
Cathodic protection and chemical inhibitors are two widely used methods to combat corrosion in New Zealand. Cathodic protection works by forcing the metal's potential into a negative region where it is stable, using either a sacrificial anode or external power supply. Chemical inhibitors remove electrons from the metal's surface, pushing its potential into a positive region where a protective oxide film forms. Both methods control the metal's surface charge to reduce corrosion.
Corrosion is the deterioration of metals due to chemical reactions with the environment. It can have serious consequences like structural failure, contamination, and equipment damage. Corrosion occurs via electrochemical reactions where the metal oxidizes (anode) and other reactions reduce (cathode). Factors like galvanic effects, stress, and aggressive ions can accelerate corrosion. Common methods to control corrosion include using coatings, alloying, removing oxygen, adding inhibitors, and electrochemical protection like cathodic protection. Proper prevention strategies can significantly extend the lifetime of metal structures and equipment.
Power plant chemistry corrosion theory and its preventionumar farooq
The document provides information about corrosion theory and prevention in power plants. It defines corrosion and discusses corrosion mechanisms such as the corrosion cell and various corrosion reactions. It also covers different types of corrosion like general corrosion, pitting, galvanic corrosion and stress corrosion cracking. Additionally, it lists factors that affect corrosion rates like dissolved gases, solids, temperature and acidity. Finally, it discusses methods of corrosion control like using corrosion inhibitors and promoting protective scales to change the corrosive environment. The document is a technical report on corrosion prepared by Umar Farooq, a chemist at SEC in Saudi Arabia.
ENGINEERING CHEMISTRY: Module 2-corrosion & its control - metal finishingrashmi m rashmi
Corrosion is the destruction of metals through chemical or electrochemical reaction with the environment. There are different types of corrosion including dry corrosion from gases, wet corrosion in liquids, galvanic corrosion between dissimilar metals, and differential aeration corrosion where parts of the same metal experience different oxygen levels. Corrosion occurs via an electrochemical process where a metal acts as the anode and undergoes oxidation, while another acts as the cathode and undergoes reduction. Factors that affect the corrosion rate include the metal type, corrosion product properties, potential differences, and environmental conditions such as temperature, pH, and conductivity. Corrosion can be controlled through methods like anodizing which forms a protective oxide layer, and phosphating
The document discusses various methods of corrosion control including material selection, alteration of environment, proper design, cathodic protection, anodic protection, and coatings & wrapping. It provides details on each method. For material selection, it discusses selecting the proper material based on the corrosive environment and lists examples of appropriate materials for common environments. It also discusses the various types of stainless steel and their alloying elements and properties.
This chapter discusses how materials interact with their environments and the various corrosion mechanisms that can occur. It describes five main types of corrosion: uniform corrosion, galvanic corrosion, pitting and crevice corrosion, hydrogen embrittlement, and stress-assisted corrosion. It also discusses methods to prevent corrosion, including material selection, design modifications, cathodic protection, and use of protective coatings. Corrosion represents a huge economic cost, so preventing its deleterious effects on materials is important for engineering applications.
This document provides an overview of biocorrosion or microbially influenced corrosion (MIC). It discusses how microbial activity within biofilms formed on metal surfaces can accelerate or inhibit corrosion through various mechanisms. Key points include:
- MIC is caused by the metabolic activities of microorganisms in biofilms, which can supply insoluble products that accept electrons from metals, accelerating corrosion.
- Many types of bacteria are implicated in MIC, including sulphate-reducing bacteria, metal-reducing bacteria, metal-depositing bacteria, and acid-producing bacteria.
- Biofilms are heterogeneous structures that can modify the local environment at the metal-biofilm interface in ways that influence corrosion kinetics.
- Dist
Corrosion, which is the degradation of material due to reactions with the environment, is usually electrochemical in nature. For this reason, an understanding of basic electrochemistry is necessary to the understanding of corrosion. Robert Heidersbach, author of "Metallurgy and Corrosion Control in Oil and Gas Production," will take you on this journey. This presentation is a sample of chapter 2 of his book, which can be found on Google Books.
This document discusses hydrogen embrittlement, which is the loss of ductility in a material caused by hydrogen absorption. It can occur in body-centered cubic and hexagonal close-packed metals when as little as 0.0001% hydrogen is absorbed. Hydrogen is introduced through processes like corrosion and welding. It causes increased strain rate sensitivity and susceptibility to delayed fracture. Several mechanisms are proposed to explain how hydrogen causes embrittlement, including hydride formation and reducing decohesion strength. Prevention techniques include reducing corrosion, using cleaner steels, baking to remove hydrogen, proper welding practices, and alloying to reduce hydrogen diffusion.
Types of Wet or Electrochemical Corrosion, Differential aeration corrosion, Galvanic corrosion, Pitting corrosion, Waterline corrosion, Crevice corrosion, Stress corrosion and their mechanisms and suitable examples.
Experimental study on corrosion of steel in soil mediumeSAT Journals
Abstract
There are many practical situation were steel is exposed to soil. Deterioration of steel in such case it depends upon the nature of soil, more especially the types and the concentration of ions present in the moisture within the soil, since soil vary in nature it is necessary to understand the nature of corrosion of steel in each of soil samples. This aspect was taken for the investigation and present in this paper. The weight and electrochemical methods of evaluating the corrosion rate were used in which four types of soil available around SRM university campus were utilized during the experimental work. Steel coupon of 12mm diameter and 100mm length was used, for each soil three artificial environments were created and electrochemical potential measuring was made for five weeks. The test shows that presence of chlorides ions in the soil create very severe environment and the drying of soil reduce the rate of corrosion.
Keywords, Corrosion of steel, Soil, Weight method, Electrochemical potential method
Inhibition of Sulphuric Acid Corrosion of Mild Steel by Surfactant and Its Ad...IOSR Journals
Abstract: The corrosion inhibition effect of surfactant, N,N-Dimethyl-N-(2-Phenoxyethyl)dodecan-1- aminiumbromide(DPDAB) on mild steel corrosion in 0.5M Sulphuric acid was investigated by weight loss, potentiodynamic polarization and Electrochemical impedance spectroscopic techniques. DPDAB is an excellent inhibitor and its inhibition efficiency increases with increase in concentration and maximum inhibition efficiency was observed above the critical micelle concentration (CMC). The polarization curves reveal that DPDAB acts as mixed type inhibitor with predominantly of anodic type. The corrosion inhibition efficiency of DPDAB increases with increase in concentration and decreases with increase in temperature from 298K to 308K and then increases and shows maxima at 318K and then decreases at 328K.. The adsorption of the inhibitor on the mild steel in 0.5M H2SO4 was found to obey Langmuir’s adsorption isotherm. Scanning electronic microscopy (SEM) confirmed the existence of an adsorbed protective film on the metal surface. The kinetic and thermodynamic parameters were calculated and discussed.
This document discusses the effects of hydrogen on tantalum and niobium materials. Small amounts of hydrogen can be absorbed by these metals, but higher levels of hydrogen absorption can lead to embrittlement and loss of ductility. The presence of hydrogen is one of the main failure mechanisms for tantalum and niobium in corrosive environments. Several methods are discussed for preventing and detecting hydrogen embrittlement in tantalum and niobium, including controlling temperatures and concentrations, using isolation kits, vacuum degassing, visual inspection of fractures, and resistivity testing. Laboratory corrosion tests were able to predict failure times of tantalum and niobium alloys in sulfuric acid environments.
This document provides an overview of surface treatment methods for aerospace components, including anodization, ultrasonic solvent cleaning, pickling-passivation, chemical cleaning, and vapour degreasing. It acknowledges those who helped with the project work. Tables of contents and figures/tables are included. The abstract indicates that tests were conducted to determine which surface treatment methods are suitable for different metals used in aerospace and whether thickness, hardness, porosity, and corrosion resistance met specifications.
CMEME2015 Conference: "Understanding hydrogen behaviour in steels" Daniel Gaude-Fugarolas
This document discusses understanding hydrogen behavior in steels, including diffusion, trapping, embrittlement risk and prevention. It covers several topics:
1. Studying hydrogen embrittlement and diffusion modeling.
2. Applications including analysis of casting processes, development of a new hydrogen extraction method during casting, analysis of baking treatments, and prediction of hydrogen damage.
3. Ongoing work on hydrogen desorption and permeation.
Hydrogen embrittlement is a phenomenon that causes metals like steel, titanium, and aluminum alloys to become brittle. It occurs when hydrogen enters these metals, reducing their ductility and load bearing capacity. There are several ways hydrogen can get into metals, such as from acid cleaning, electroplating, welding, and heat treating. Once hydrogen is absorbed, even small amounts below detection levels can cause cracking or failure of parts, especially under stress. Proper baking and controlling hydrogen exposure during manufacturing processes can help prevent failures from hydrogen embrittlement.
The document discusses a workshop focused on developing corrosion resistant alloys for naval aviation applications. It provides background on the harsh corrosive environment aircraft operate in for the Navy and Marine Corps. The workshop brought together experts to identify goals, objectives, challenges and approaches for three alloy systems: aluminum, magnesium, and steel. For each alloy system, the group validated objectives, identified technical challenges, and prioritized approaches to overcome the challenges. Critical research areas were established that could help achieve the objectives and advance the development of corrosion resistant alloys for naval aviation.
The aim of this project was to investigate and evaluate corrosion using computer modelling for investigating causes of failure on specimen which had similar behavior to nature of failures, used in petroleum industry. A nipple-connecter reducer made from malleable cast iron used to carry liquid and gas in a petro chemical company located in Bahrain was used as sample.
The problem was also modeled to study the effect of the flow in causing the corrosion, in the nipple-connecter reducer assembly which concludes that the main cause of this attack is the flow turbulence, shear stress and pressure.
The document discusses corrosion, which is the gradual destruction of metals through chemical or electrochemical reaction with the environment. Rusting of iron is a common example. There are two main types of corrosion - direct chemical corrosion which occurs through reaction with gases, and electrochemical corrosion which occurs when a metal is in contact with a conducting liquid. Electrochemical corrosion results from the formation of galvanic cells and the flow of current between anodic and cathodic areas. Methods of controlling corrosion include selecting corrosion-resistant materials, using protective coatings like paints and anodizing, adding corrosion inhibitors, and cathodic protection techniques.
Hydrogen embrittlement of metals occurs when hydrogen interacts with and degrades the material properties of metals. There are three main mechanisms of hydrogen embrittlement: hydride formation and cracking, hydrogen-enhanced decohesion along grain boundaries, and hydrogen-enhanced localized plasticity. Preventing hydrogen embrittlement requires reducing corrosion and hydrogen exposure to the metal, changing electroplating processes, heat-treating materials to remove hydrogen, and using inherently less susceptible materials. High-strength steels are particularly susceptible to hydrogen embrittlement.
1. Corrosion is the deterioration and loss of solid metallic material by chemical or electrochemical attack by its environment.
2. There are two main types of corrosion: dry/chemical corrosion which occurs through direct chemical action, and wet/electrochemical corrosion which occurs when a conducting liquid is in contact with the metal.
3. Wet corrosion occurs via separate anodic and cathodic reactions - the anodic reaction involves metal dissolution or compound formation, while the cathodic reaction involves hydrogen evolution in acidic environments or oxygen absorption in basic environments.
In the present investigation the corrosion measurements were carried out in 5% NaCl
aqueous solution, 2.5% HCl. solution for predetermined time intervals and varying
percentage concentrations of HCl solution at room temperature. Kinetics of corrosion
effect on samples of Al-Zn alloy, Al-Zn –5wt% flyash and silicon carbide particles and
Al-Zn –10wt% flyash and silicon carbide particles as reinforcement in composite are
studied.
The document discusses corrosion and oxidation of metals, including the principles behind corrosion and methods for preventing corrosion. It describes how metals oxidize when exposed to oxygen and how the formation and properties of metal oxides, such as their adherence and volume, influence corrosion rates. Factors that affect oxidation rates and the development of protective oxide layers are covered. Methods for improving corrosion resistance through alloying and the use of coatings or inhibitors are also summarized.
This document is a chapter-by-chapter summary of a document on cathodic protection of pipelines. It discusses the principles of corrosion, forms of corrosion including uniform, galvanic, crevice, pitting and stress corrosion cracking. It explains the mechanisms and prevention methods for different forms of corrosion. The document is intended to provide an overview of corrosion and cathodic protection for pipelines.
Corrosion is the deterioration of metals through chemical reactions with the environment. It can structurally weaken materials and equipment, contaminate systems, and is costly to prevent and repair. Corrosion occurs via electrochemical processes where metals oxidize (rust), releasing electrons. Factors like water chemistry, oxygen levels, temperature, and contact with other metals influence corrosion rates. Prevention methods include coating metals, alloying them, inhibiting reactions, or electrochemically controlling corrosion through cathodic protection. Proper material selection, design, and maintenance can significantly extend product lifetimes and reduce corrosion impacts.
ENGINEERING CHEMISTRY: Module 2-corrosion & its control - metal finishingrashmi m rashmi
Corrosion is the destruction of metals through chemical or electrochemical reaction with the environment. There are different types of corrosion including dry corrosion from gases, wet corrosion in liquids, galvanic corrosion between dissimilar metals, and differential aeration corrosion where parts of the same metal experience different oxygen levels. Corrosion occurs via an electrochemical process where a metal acts as the anode and undergoes oxidation, while another acts as the cathode and undergoes reduction. Factors that affect the corrosion rate include the metal type, corrosion product properties, potential differences, and environmental conditions such as temperature, pH, and conductivity. Corrosion can be controlled through methods like anodizing which forms a protective oxide layer, and phosphating
The document discusses various methods of corrosion control including material selection, alteration of environment, proper design, cathodic protection, anodic protection, and coatings & wrapping. It provides details on each method. For material selection, it discusses selecting the proper material based on the corrosive environment and lists examples of appropriate materials for common environments. It also discusses the various types of stainless steel and their alloying elements and properties.
This chapter discusses how materials interact with their environments and the various corrosion mechanisms that can occur. It describes five main types of corrosion: uniform corrosion, galvanic corrosion, pitting and crevice corrosion, hydrogen embrittlement, and stress-assisted corrosion. It also discusses methods to prevent corrosion, including material selection, design modifications, cathodic protection, and use of protective coatings. Corrosion represents a huge economic cost, so preventing its deleterious effects on materials is important for engineering applications.
This document provides an overview of biocorrosion or microbially influenced corrosion (MIC). It discusses how microbial activity within biofilms formed on metal surfaces can accelerate or inhibit corrosion through various mechanisms. Key points include:
- MIC is caused by the metabolic activities of microorganisms in biofilms, which can supply insoluble products that accept electrons from metals, accelerating corrosion.
- Many types of bacteria are implicated in MIC, including sulphate-reducing bacteria, metal-reducing bacteria, metal-depositing bacteria, and acid-producing bacteria.
- Biofilms are heterogeneous structures that can modify the local environment at the metal-biofilm interface in ways that influence corrosion kinetics.
- Dist
Corrosion, which is the degradation of material due to reactions with the environment, is usually electrochemical in nature. For this reason, an understanding of basic electrochemistry is necessary to the understanding of corrosion. Robert Heidersbach, author of "Metallurgy and Corrosion Control in Oil and Gas Production," will take you on this journey. This presentation is a sample of chapter 2 of his book, which can be found on Google Books.
This document discusses hydrogen embrittlement, which is the loss of ductility in a material caused by hydrogen absorption. It can occur in body-centered cubic and hexagonal close-packed metals when as little as 0.0001% hydrogen is absorbed. Hydrogen is introduced through processes like corrosion and welding. It causes increased strain rate sensitivity and susceptibility to delayed fracture. Several mechanisms are proposed to explain how hydrogen causes embrittlement, including hydride formation and reducing decohesion strength. Prevention techniques include reducing corrosion, using cleaner steels, baking to remove hydrogen, proper welding practices, and alloying to reduce hydrogen diffusion.
Types of Wet or Electrochemical Corrosion, Differential aeration corrosion, Galvanic corrosion, Pitting corrosion, Waterline corrosion, Crevice corrosion, Stress corrosion and their mechanisms and suitable examples.
Experimental study on corrosion of steel in soil mediumeSAT Journals
Abstract
There are many practical situation were steel is exposed to soil. Deterioration of steel in such case it depends upon the nature of soil, more especially the types and the concentration of ions present in the moisture within the soil, since soil vary in nature it is necessary to understand the nature of corrosion of steel in each of soil samples. This aspect was taken for the investigation and present in this paper. The weight and electrochemical methods of evaluating the corrosion rate were used in which four types of soil available around SRM university campus were utilized during the experimental work. Steel coupon of 12mm diameter and 100mm length was used, for each soil three artificial environments were created and electrochemical potential measuring was made for five weeks. The test shows that presence of chlorides ions in the soil create very severe environment and the drying of soil reduce the rate of corrosion.
Keywords, Corrosion of steel, Soil, Weight method, Electrochemical potential method
Inhibition of Sulphuric Acid Corrosion of Mild Steel by Surfactant and Its Ad...IOSR Journals
Abstract: The corrosion inhibition effect of surfactant, N,N-Dimethyl-N-(2-Phenoxyethyl)dodecan-1- aminiumbromide(DPDAB) on mild steel corrosion in 0.5M Sulphuric acid was investigated by weight loss, potentiodynamic polarization and Electrochemical impedance spectroscopic techniques. DPDAB is an excellent inhibitor and its inhibition efficiency increases with increase in concentration and maximum inhibition efficiency was observed above the critical micelle concentration (CMC). The polarization curves reveal that DPDAB acts as mixed type inhibitor with predominantly of anodic type. The corrosion inhibition efficiency of DPDAB increases with increase in concentration and decreases with increase in temperature from 298K to 308K and then increases and shows maxima at 318K and then decreases at 328K.. The adsorption of the inhibitor on the mild steel in 0.5M H2SO4 was found to obey Langmuir’s adsorption isotherm. Scanning electronic microscopy (SEM) confirmed the existence of an adsorbed protective film on the metal surface. The kinetic and thermodynamic parameters were calculated and discussed.
This document discusses the effects of hydrogen on tantalum and niobium materials. Small amounts of hydrogen can be absorbed by these metals, but higher levels of hydrogen absorption can lead to embrittlement and loss of ductility. The presence of hydrogen is one of the main failure mechanisms for tantalum and niobium in corrosive environments. Several methods are discussed for preventing and detecting hydrogen embrittlement in tantalum and niobium, including controlling temperatures and concentrations, using isolation kits, vacuum degassing, visual inspection of fractures, and resistivity testing. Laboratory corrosion tests were able to predict failure times of tantalum and niobium alloys in sulfuric acid environments.
This document provides an overview of surface treatment methods for aerospace components, including anodization, ultrasonic solvent cleaning, pickling-passivation, chemical cleaning, and vapour degreasing. It acknowledges those who helped with the project work. Tables of contents and figures/tables are included. The abstract indicates that tests were conducted to determine which surface treatment methods are suitable for different metals used in aerospace and whether thickness, hardness, porosity, and corrosion resistance met specifications.
CMEME2015 Conference: "Understanding hydrogen behaviour in steels" Daniel Gaude-Fugarolas
This document discusses understanding hydrogen behavior in steels, including diffusion, trapping, embrittlement risk and prevention. It covers several topics:
1. Studying hydrogen embrittlement and diffusion modeling.
2. Applications including analysis of casting processes, development of a new hydrogen extraction method during casting, analysis of baking treatments, and prediction of hydrogen damage.
3. Ongoing work on hydrogen desorption and permeation.
Hydrogen embrittlement is a phenomenon that causes metals like steel, titanium, and aluminum alloys to become brittle. It occurs when hydrogen enters these metals, reducing their ductility and load bearing capacity. There are several ways hydrogen can get into metals, such as from acid cleaning, electroplating, welding, and heat treating. Once hydrogen is absorbed, even small amounts below detection levels can cause cracking or failure of parts, especially under stress. Proper baking and controlling hydrogen exposure during manufacturing processes can help prevent failures from hydrogen embrittlement.
The document discusses a workshop focused on developing corrosion resistant alloys for naval aviation applications. It provides background on the harsh corrosive environment aircraft operate in for the Navy and Marine Corps. The workshop brought together experts to identify goals, objectives, challenges and approaches for three alloy systems: aluminum, magnesium, and steel. For each alloy system, the group validated objectives, identified technical challenges, and prioritized approaches to overcome the challenges. Critical research areas were established that could help achieve the objectives and advance the development of corrosion resistant alloys for naval aviation.
The aim of this project was to investigate and evaluate corrosion using computer modelling for investigating causes of failure on specimen which had similar behavior to nature of failures, used in petroleum industry. A nipple-connecter reducer made from malleable cast iron used to carry liquid and gas in a petro chemical company located in Bahrain was used as sample.
The problem was also modeled to study the effect of the flow in causing the corrosion, in the nipple-connecter reducer assembly which concludes that the main cause of this attack is the flow turbulence, shear stress and pressure.
The document discusses corrosion, which is the gradual destruction of metals through chemical or electrochemical reaction with the environment. Rusting of iron is a common example. There are two main types of corrosion - direct chemical corrosion which occurs through reaction with gases, and electrochemical corrosion which occurs when a metal is in contact with a conducting liquid. Electrochemical corrosion results from the formation of galvanic cells and the flow of current between anodic and cathodic areas. Methods of controlling corrosion include selecting corrosion-resistant materials, using protective coatings like paints and anodizing, adding corrosion inhibitors, and cathodic protection techniques.
Hydrogen embrittlement of metals occurs when hydrogen interacts with and degrades the material properties of metals. There are three main mechanisms of hydrogen embrittlement: hydride formation and cracking, hydrogen-enhanced decohesion along grain boundaries, and hydrogen-enhanced localized plasticity. Preventing hydrogen embrittlement requires reducing corrosion and hydrogen exposure to the metal, changing electroplating processes, heat-treating materials to remove hydrogen, and using inherently less susceptible materials. High-strength steels are particularly susceptible to hydrogen embrittlement.
1. Corrosion is the deterioration and loss of solid metallic material by chemical or electrochemical attack by its environment.
2. There are two main types of corrosion: dry/chemical corrosion which occurs through direct chemical action, and wet/electrochemical corrosion which occurs when a conducting liquid is in contact with the metal.
3. Wet corrosion occurs via separate anodic and cathodic reactions - the anodic reaction involves metal dissolution or compound formation, while the cathodic reaction involves hydrogen evolution in acidic environments or oxygen absorption in basic environments.
In the present investigation the corrosion measurements were carried out in 5% NaCl
aqueous solution, 2.5% HCl. solution for predetermined time intervals and varying
percentage concentrations of HCl solution at room temperature. Kinetics of corrosion
effect on samples of Al-Zn alloy, Al-Zn –5wt% flyash and silicon carbide particles and
Al-Zn –10wt% flyash and silicon carbide particles as reinforcement in composite are
studied.
The document discusses corrosion and oxidation of metals, including the principles behind corrosion and methods for preventing corrosion. It describes how metals oxidize when exposed to oxygen and how the formation and properties of metal oxides, such as their adherence and volume, influence corrosion rates. Factors that affect oxidation rates and the development of protective oxide layers are covered. Methods for improving corrosion resistance through alloying and the use of coatings or inhibitors are also summarized.
This document is a chapter-by-chapter summary of a document on cathodic protection of pipelines. It discusses the principles of corrosion, forms of corrosion including uniform, galvanic, crevice, pitting and stress corrosion cracking. It explains the mechanisms and prevention methods for different forms of corrosion. The document is intended to provide an overview of corrosion and cathodic protection for pipelines.
Corrosion is the deterioration of metals through chemical reactions with the environment. It can structurally weaken materials and equipment, contaminate systems, and is costly to prevent and repair. Corrosion occurs via electrochemical processes where metals oxidize (rust), releasing electrons. Factors like water chemistry, oxygen levels, temperature, and contact with other metals influence corrosion rates. Prevention methods include coating metals, alloying them, inhibiting reactions, or electrochemically controlling corrosion through cathodic protection. Proper material selection, design, and maintenance can significantly extend product lifetimes and reduce corrosion impacts.
Design, Management and Key Success Factors of an Offshore Cathodic Protection...Dr. Amarjeet Singh
Corrosion is a very prevalent issue for offshore
operations in the oil and gas industry. If the corrosion issues
are not addressed adequately, these may lead to quality
failures, safety incidents, compromise to asset integrity and
high inspection costs. This research paper discusses and
analyzes corrosion types, corrosion threats, mechanisms to
protect against corrosion, design and management of cathodic
protection system, and key success factors for a cathodic
protection system for an offshore oil and gas production
system.
Definitions, Major Causes of Corrosion,Other Causes of Corrosion, Forms Of Corrosion, How Does corrosion Happen ?,The Process of Corrosion (Five facts)
Measurement of Corrosion.
Corrosion Rate.
Comparison between Different metals.
Corrosion Prevention.
Corrosion monitoring.
Side effects of Prevention Methods.
Conclusion.
The document defines corrosion and discusses its major types and economic impacts. It begins by defining corrosion as the deterioration of metals due to chemical or electrochemical reaction with their environment. It then discusses several types of corrosion including uniform corrosion, galvanic corrosion, pitting corrosion, crevice corrosion, dealloying, and stress corrosion cracking. It explains the mechanisms and examples of each type. The document emphasizes that corrosion has huge economic costs, with estimates of 3-3.5% of GDP lost to corrosion in India and the US each year.
Corrosion is a natural process that deteriorates materials, commonly metals, due to chemical or electrochemical reactions with their environment. It's a significant concern across various industries, including infrastructure, manufacturing, and transportation. The effects of corrosion can range from minor aesthetic damage to catastrophic structural failure, leading to enormous economic costs and safety hazards.
Several factors influence corrosion, including environmental conditions such as moisture, temperature, pH levels, and the presence of corrosive agents like oxygen, sulfur compounds, and salts. Additionally, the material's composition and microstructure play crucial roles in its susceptibility to corrosion.
To mitigate corrosion and prolong the lifespan of materials, various protection methods are employed:
Barrier Protection: This involves applying coatings or barriers to physically isolate the material from its environment. Common barrier materials include paints, polymer coatings, and enamels. These coatings create a protective layer that prevents corrosive agents from reaching the underlying material.
Cathodic Protection: This method involves making the metal to be protected the cathode of an electrochemical cell, thus reducing its corrosion rate. Cathodic protection can be achieved through sacrificial anodes, where a more reactive metal (such as zinc or magnesium) is connected to the metal to be protected, sacrificing itself to protect the base metal.
Anodic Protection: Conversely, anodic protection works by polarizing the metal to be protected to make it the anode in an electrochemical cell. This method is suitable for metals that exhibit passivity, such as stainless steel. By maintaining the metal in its passive state, its corrosion rate is significantly reduced.
Inhibitors: Corrosion inhibitors are chemicals that are added to the environment surrounding the metal to reduce its corrosion rate. Inhibitors work by adsorbing onto the metal surface, forming a protective layer that blocks corrosive agents from reaching the metal. Common inhibitors include organic compounds, chromates, and phosphates.
Alloying: Alloying involves mixing the base metal with other elements to improve its corrosion resistance. For example, stainless steel contains chromium, which forms a passive oxide layer on the surface, protecting the underlying metal from corrosion.
Design Modification: Sometimes, corrosion can be mitigated through design modifications that minimize exposure to corrosive environments or improve drainage to prevent the accumulation of moisture.
Each protection method has its advantages and limitations, and the choice of method depends on factors such as the material, the environment, cost considerations, and the required durability. In many cases, a combination of protection methods may be employed to provide optimal corrosion resistance.
Corrosion is the degradation of materials due to chemical reactions with their surroundings. Metals are particularly susceptible to corrosion, which can occur electrochemically through oxidation or by other chemical processes. Corrosion can damage structures and infrastructure, costing an estimated $276 billion annually in the US alone. Common forms of corrosion include rust, which weakens bridges and causes failures, and glass disease, where aqueous solutions cause corrosion of silicate glasses. Protective measures like passivation and materials selection aim to reduce corrosion and its economic impacts.
There are several types of corrosion that can occur:
1. Uniform and galvanic corrosion which results from direct chemical attack or from dissimilar metals in contact being exposed to an electrolyte.
2. Erosion corrosion caused by abrasive fluid flow removing a metal's protective surface film.
3. Crevice and pitting corrosion which are localized forms of corrosion occurring in cracks, crevices or defects in a metal surface.
4. Intergranular corrosion which attacks grain boundaries in metals or alloys.
5. Other forms include exfoliation, selective leaching, stress corrosion cracking, waterline corrosion affecting ship hulls, soil corrosion depending on soil conditions, and microbiologically influenced corrosion caused by
Comparative Investigation of Inhibitive Properties of Newbouldia Laevis (NL) ...IRJET Journal
This document summarizes a study that compares the inhibitive properties of Newbouldia Laevis (NL) and Azadirachta Indica (AZI) leaf extracts on corrosion of high carbon steel in sulphuric acid. Using the gravimetric method, the extracts were tested at various concentrations to determine their effectiveness at preventing corrosion. The study found that NL leaf extract was a more effective inhibitor, achieving 88% efficiency at 0.5g/L, while AZI achieved 71% efficiency at the same concentration. This shows that NL leaf extract is a better corrosion inhibitor for high carbon steel in sulphuric acid than AZI leaf extract.
Pitting corrosion is an insidious localized form of corrosion causing much devastating
destruction to structural members such as stainless steel in chloride environment. This
paper gives a review of the mechanism processes of pitting, stages, factors facilitating
pitting corrosion, techniques of evaluating pitting corrosion and some research work on
pitting corrosion. The rudimentary knowledge of the mechanisms of pitting corrosion from
this work will be of assistance to the selection process, specification and the use of stainless
steels and other structural members.
1. Corrosion is the primary means by which metals deteriorate when exposed to various environments like water, acids, bases, salts, oils, gases, and other chemicals. Understanding metallurgical factors that influence corrosion, like chemical composition, material structure, alloying elements, and heat treatment, is important for controlling corrosion in industries like petroleum and chemicals.
2. Key metallurgical factors that affect corrosion include the chemical composition, material structure, grain boundaries, alloying elements, mechanical properties, heat treatment, surface coating, welding, and manufacturing conditions of metals and alloys.
3. Common forms of corrosion include general corrosion, localized corrosion, intergranular corrosion, stress corrosion cracking, and corrosion
this slide comprises of definition.rate, and types of corrosion which are found in materials in our daily life.
its contents are:
what is corrosion
what are its basic types and
what is the rate of corrosion in materials
The document discusses different types of corrosion and how to calculate corrosion rates. It describes 10 common types of corrosion including general attack, localized pitting and crevice corrosion, galvanic corrosion, stress corrosion cracking, and high temperature corrosion. It also explains that corrosion rates depend on factors like weight loss, metal density, surface area, and time, and can be determined using electrochemical measurements and Faraday's law.
APPLICATION OF WASTE NATURAL MATERIAL FOR CORROSION INHIBITION OF LOW CARBON ...IRJET Journal
This document summarizes research on using waste natural materials as corrosion inhibitors for low carbon steel in NaCl solutions. Specifically, it investigates the inhibitory effects of onion peel extracts in 1.5M NaCl solution. Testing methods like weight loss measurements, polarization techniques and SEM imaging were used to analyze the protective film formed by onion peel compounds adsorbed on the steel surface. Results found the aqueous onion peel extract inhibited over 90% of corrosion. The researchers concluded onion peel is a promising green corrosion inhibitor for low carbon steel in NaCl environments. Future work could study individual bioactive compounds in onion peel and developing coating layers from extract-treated surfaces.
The document discusses different types of corrosion and how to calculate corrosion rates. It describes 10 common types of corrosion including general attack, localized pitting and crevice corrosion, galvanic corrosion, stress corrosion cracking, and high temperature corrosion. It also explains that corrosion rates depend on factors like weight loss, metal density, surface area, and time, and can be determined using electrochemical measurements and Faraday's law.
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Introduction to Industrial Corrosion
1. FIN 624 Fundamental of Industrial Corrosion
Final Presentation Submitted to The Academic Department
Of the School of Science and Engineering
In Partial Fulfillment of the Requirements
For the Doctorial Degree in Mechanical Engineering
ATLANTIC INTERNATIONAL UNIVERSITY
Yasir Dhaif Mahdi Alnaseri
ID# UD67080SME76152
1
3. Corrosive Environment
Many parameters could seriously affect the material where it is in a
specific environment.
The effects may make significant changes in the chemical
composition of the material.
Corrosion environment can be classified into two categories based on
the type of environment:
- Natural Environment (rain, snow, humidity, marine
environment, etc.)
- Harmful People Made Environment (road salts, air pollutions,
industrial emission, acidic rain, etc.)
3
4. Corrosive Environment
Corrosive Environment can be categorized into several kinds
depending on its nature, such as:
- Atmospheric,
- Soil,
- Water,
- Acidic,
- Alkaline,
- and the combination (mixing) of all the above types.
Corrosion represents one of the most serious noticed in the industrial
world especially in petrochemical, petroleum, power plants, etc.
Billions of Dollars are lost yearly due to the affect of corrosion in the
world.
4
5. Corrosive Environment
Characteristics of The Corrosive Environment
- Degree of alkalinity or acidity
- Electrochemical potential
- Temperature of the environment
- Flow rate of the fluid
- Concentration of the corrodent
- Biological organism
5
6. Corrosive Environment
Figure 1. Effect of pH Vs. Corrosion Rate.
Adapted from Biplob Kumar Biswas From Jessore University Of Science &
Technology(JUST),Bangladesh, 2015, retrieved from
https://www.slideshare.net/rayhan_u01/corrosion-engineering-54230652
6
8. Corrosive Environment
Figure 3. Flow Rate of The Fluid Effects
Prof. T. K. G. Namboodhiri, The presentation deals with our study on the velocity
affected corrosion of a line-pipe steel, API-X52 in sea water environment, Published
on December 2nd, 2009, https://image.slidesharecdn.com/velocity-
assistedcorrosionofapix-52steelin3-091202084016-phpapp01/95/velocity-assisted-
corrosion-of-api-x-52-steel-in-3-5-728.jpg?cb=1259743284 8
9. Corrosive Environment
Figure 4. Concentration of The Corrodent Effects (Chloride as example)
Prawoto, Yunan & Ibrahim, Khaled & wan nik, wan sani. (2009). Effect
of ph and chloride concentration on the corrosion of duplex stainless
steel. Arabian Journal for Science and Engineering. 34.
9
10. Corrosive Environment
Figure 5. Biological Organism Effects
Javed, Muhammad Awais & Neil, W & McAdam, G & Wade, Scott.
(2016). MICROBIOLOGICALLY INFLUENCED CORROSION OF
COPPER AND ITS ALLOYS – A REVIEW.
10
12. Corrosion Definition
There are several definitions for the corrosions, but they give the same
meaning and understanding. Corrosion is:
The process of deterioration of a substance due to chemical, electrochemical
or other reactions takes place on the surface of the substance.
Or, a natural process, which converts a refined metal to their more stable
oxide.
Or, a deterioration of a material due to the electrochemical reaction between
the material and its environment.
Or, the degradation of a material due to the interaction with the surrounding
environment or medium. 12
13. Corrosion Definition
Figure 6. Corrosion Example
Forsyth, P & Robert, D.J. & Rajeev, Pat & Li, Chun Qing. (2014).
Codified methods to analyse the failures of water pipelines: A Review.
13
14. Corrosion Mechanism
Based on the mechanism of corrosion, corrosion can divide into
two types:
Electrochemical Corrosion (Electrolyte is required to preform this type)
Chemical Corrosion (Electrolyte is not required)
14
15. Corrosion Mechanism
Electrochemical Corrosion:
It called also Wet Corrosion, Aqueous Corrosion, and Low Temperature
Corrosion.
Occurs through the formation of cell.
Happens only on the heterogeneous metal surface.
Non-uniform corrosion.
It takes place when the medium temperature below 204 C.
Corrosion products accumulates on the cathode.
15
16. Corrosion Mechanism
Four factors should be available to produce the electrochemical corrosion:
1. Metal loss must be occurred.
2. Electrons must transfer from another metal.
3. Reaction should be taking place.
4. The electrolyte is mandatory as a transfer medium for the
consumed ions.
Electrochemical Corrosion
16
17. Corrosion Mechanism
Example 1:
In the petroleum refining industry, the corrosion takes place by the
electrochemical corrosion. The mechanism of this corrosion is very complicated
because the electrodes are not connected by wire. For example, inside the
carbon steel pipe, there is innumerable microlevel of Anodes and Cathodes cells
represented by Iron (Fe Anode) and Iron Carbide (Cathode Fe3C); at this point,
each metal is usually conducted of an electron, that is mean, only the electrolyte
medium is required to complete the life cycle of the corrosion process inside the
carbon steel pipe. Crude oil, waste-water, petroleum residue, and row water
illustrate the most electrolyte fluids in the Oil and Gas industry.
Electrochemical Corrosion
17
18. Corrosion Mechanism
Example 2:
When the pure metal works at two different temperatures.
Temperature difference may affect the metal so that at one will be Anode
and at the different will act as Cathode. Moreover, the electrolyte
concentration may play critical factors in the electrochemical corrosion.
This factor directly affects the grain boundary of the pure metal or
material, causing corrosion when the metal or the material surface in-
direct contact with the electrolyte.
Electrochemical Corrosion
18
19. Corrosion Mechanism
Figure 7. The Electrochemical Corrosion
qi, Wang & Jia, Y. & Wang, M. & Qi, Weihong & Pang, Yong & Cui, X. & Ji, Wenhai &
Yi, Jiang. (2015). Synthesis of Cu2O Nanotubes with Efficient Photocatalytic Activity
by Electrochemical Corrosion Method. The Journal of Physical Chemistry C. 119.
10.1021/acs.jpcc.5b06213.
Electrochemical Corrosion
19
20. Corrosion Mechanism
Chemical Corrosion:
It is also called Dry Corrosion and High-Temperature
Corrosion.
Takes place by direct chemical attack.
Happens on the heterogeneous and homogeneous metal
surface.
Uniform corrosion.
Occurs above the dew point of the chemical fluids or
204 C.
Corrosion product accumulates at the spot.
20
22. General Corrosion
It called general corrosion or uniform corrosion
Corrosion proceeds uniformly over the metal surface
The anode areas move to different locations until the entire
metal surface become anodic at the same time
The corrosive environment plays a critical factor in the
corrosion rate such as the motion relative to the metal
surface, temperature, concentration, acidity, and etcetera
22
23. General Corrosion
Figure 8. General Corrosion
Alhaboubi, Naseer. (2014). PERFORMANCE OF CATHODIC PROTECTION FOR PIPE LINES. 10.13140/RG.2.1.2157.2884.23
24. Galvanic Corrosion
It called galvanic because the entire system behaves as a
galvanic cell.
It takes place when the dissimilar metals are in electrical
contact in an electrolyte.
The less noble metal is attacked to a greater degree than if it
were exposed alone.
Usually appears as furrows or troughs on the corroded metal
at the point of contact with the more noble metal.
24
26. Concentration-Cell Corrosion
It is also called Crevice corrosion.
Concentration-cells are formed whenever the dissolved oxygen is
not uniform throughout the entire solution.
When two dissimilar metals joint together cause deterioration, so
do different conditions within the electrolyte.
It happens due to various substances in the solutions or to varying
concentrations of these substances.
In general, Metal in more concentrated solutions is anodic to
metals in contact with diluted parts of the solution.
26
27. Concentration-Cell Corrosion
Figure 10. Concentration-Cell Corrosion
Farotade, Gabriel & Popoola, Patricia & Popoola, Olawale. (2016). Computational
Analysis of System and Design Parameters of Electrodeposition for Marine
Applications. 10.5772/62376.
27
28. Intergranular Corrosion
Consists of a localized attack along the grain boundaries of a metal or alloy.
The corrosion can proceed to the point where whole grains of metal falls away,
and the metal loses its strength through a redaction in cross-section.
Improper heat transfer or heat from welding that causes the precipitation of
alloy components at the grain boundary is the usual cause of this type of
corrosion.
The precipitation causes a depletion of corrosion-resisting elements in the area
surrounding the grain boundary, and the area becomes anodic to the remainder
of grain.
This form of attack is most familiar with austenitic steels.
28
29. Intergranular Corrosion
Figure 11. Intergranular Corrosion
Du Toit, Madeleine & van Rooyen, Gerrit & Smith, D.. (2007). Heat-Affected Zone Sensitization and Stress
Corrosion Cracking in 12% Chromium Type 1.4003 Ferritic Stainless Steel. Corrosion. 63. 10.5006/1.3278392.29
30. Stress Corrosion Crack
It occurs in weldments when susceptible microstructure, surface
tensile stresses, and corrosion media are simultaneously present.
It often progresses rapidly and is more common among alloys than
pure metals.
It leads to unexpected and sudden failure of ordinarily ductile metal
alloys subjected to tensile stress, especially at elevated temperatures.
The heat or energy input influences the weld deposit's size and
geometry, welding parameters, and procedures that affect the
amount and distribution of residual stress present in the weld. 30
32. Pitting
It takes place due to the reduction of the protective thin passive
oxide film.
It represents a type of localized corrosive attack.
It results from a concentration-cell formed from variations in a
solution composition in contact with the metal.
The pit acts as an anode supported by surrounding large cathodic
areas.
When the solution or the material combination, or both, reach a
potential that exceeds a critical value termed the pitting potential. 32
33. Pitting
Figure 13. Pitting
Honarvar Nazari, Mehdi & Shi, Xianming. (2018). Vehicle Risks of
Winter Road Operations and Best Management Practices.
10.1002/9781119185161.ch12.
33
34. Method to Control Corrosion
There are five principle methods to control corrosion:
Material selection
Coating
Inhibitors
Cathodic protection
Design
34
35. Material Selection
Material divided into two parts depending on its corrosion
behavior: the high corrosion resistance of noble metals (such as
gold and platinum) and the low corrosion resistance (such as
sodium and magnesium).
The material selection represents a key factor, especially when
the economic issues are considered part of the design criteria.
Corrosion behavior of the environment, corrosion rate, and
corrosion resistance of the metals illustrate the principal factors
considered in material selection for the optimum design.
35
36. Coating
The corrosion protection by coating represents one of the
most efficient methods of metal protection.
Coating protection can be categories into two groups:
metallic and non-metallic.
Coating layers (Which applied to the surface of an object) is
responsible for isolating the material surface from the
corrosive environment.
36
37. Cathodic Protection
Cathodic protection is a widespread way that widely appropriates to
protect the material against corrosion.
This technique works on converting the active areas on the object (a
metal) surface to passive.
An object works as a cathode of an Electrochemical cell.
There are two practical application methods to achieve cathodic
protection: an impressed-current system and a sacrificial-anode system.
37
38. Design
An object design can eliminate several parameters that may lead to
corrosion that could reduce the time and cost of repair and damage
due to the corrosion.
Corrosion damage is anticipated, the object design can provide
maximum interchangeability of critical components and
standardization of parts.
The interchangeability and part standardization are essential,
especially in the regions that required periodic cleaning and
maintenance.
38
39. Factors Influencing The Cost
Corrosion
Applied current technology
Deferred maintenance
Increased performance requirements
Technology transfer
Extensions of useful life
Research and development
Environmental regulations
More hostile environment
39
40. Factors Influencing The Cost
Corrosion
Corrosion costs are decreased by the application of available corrosion technology,
which is reinforced by technology transfer.
New and enhanced corrosion technology results from research and development.
The proper application of ways to control corrosion reduces the cost of corrosion.
Corrosion costs tend to increase with such factors as deferred maintenance and
extended the useful life of building and equipment.
Increased corrosion casts are realized when higher-performance specifications and
more hostile environments are encountered.
Government regulations lead to a significant increment in corrosion costs.
40
41. Diagnosis of Corrosion Failures
Several Techniques apply to monitor and diagnosis the corrosion
failures in industrial life, such as:
Visual and microscopic testing of the corroded surfaces and the
microstructure.
The chemical analysis of the metal, corrosion products, and bulk
environment.
NDT or NDE evaluation methods.
Corrosion testing techniques.
Mechanical testing techniques.
41