Studies on Corrosion Characteristics of Carbon Steel Exposed to Na2CO3, Na2SO...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
CMEME2015 Conference: "Understanding hydrogen behaviour in steels" Daniel Gaude-Fugarolas
Invited Plenary Presentation at CMEME2015 Conference in Biskra, Algeria, 8-9Dec2015.
ABSTRACT:
Small amounts of hydrogen can sometimes cause embrittlement of high strength alloys. Because of their technological and economic relevance, intense research is underway worldwide to improve our understanding of such phenomena.
A physical model has been used to study hydrogen behaviour during manufacturing of metallic alloys. In particular, the present model contemplates diffusion in its most comprehensive description, i.e., atom diffusion being driven by the gradient in chemical activation, instead of simply occurring down a composition gradient. The model incorporates as well the influence of thermal history, microstructure, matrix solubility, multiple trapping distributions, and interaction with the atmosphere.
Using this model is possible to describe and predict the behaviour of hydrogen in metals during real industrial processes. For instance, it explains the effect on hydrogen redistribution of parameters like treatment conditions, component size and microstructure, phase transformation temperature, grain size, carbide distribution, deformation level, etc.
Furthermore, a set of criteria have been developed to anticipate defect formation and embrittlement risk, based on hydrogen supersaturation.
Last but not least, a method has been developed during this work, which enables to reduce hydrogen content from the metal via the use of imposed temperature gradients. This method has recently obtained several patents.
NACE is the corrosion engineer institute. As now, material corrosion exist in our daily life, no matter in the industry application or usual commercial product. They all suffer corrosion impact. As one of member valve industry, I would like to introduce NACE and its related code in upstream and downstream area for stimulating more idea and opponent for make our working environment safe and green.
This is a presentation on hydrogen induced cracking ,sulfide stress cracking and test procedure for HIC resistant steel
DENZIL D’SOUZA
denzil22@gmail.com
Studies on Corrosion Characteristics of Carbon Steel Exposed to Na2CO3, Na2SO...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
CMEME2015 Conference: "Understanding hydrogen behaviour in steels" Daniel Gaude-Fugarolas
Invited Plenary Presentation at CMEME2015 Conference in Biskra, Algeria, 8-9Dec2015.
ABSTRACT:
Small amounts of hydrogen can sometimes cause embrittlement of high strength alloys. Because of their technological and economic relevance, intense research is underway worldwide to improve our understanding of such phenomena.
A physical model has been used to study hydrogen behaviour during manufacturing of metallic alloys. In particular, the present model contemplates diffusion in its most comprehensive description, i.e., atom diffusion being driven by the gradient in chemical activation, instead of simply occurring down a composition gradient. The model incorporates as well the influence of thermal history, microstructure, matrix solubility, multiple trapping distributions, and interaction with the atmosphere.
Using this model is possible to describe and predict the behaviour of hydrogen in metals during real industrial processes. For instance, it explains the effect on hydrogen redistribution of parameters like treatment conditions, component size and microstructure, phase transformation temperature, grain size, carbide distribution, deformation level, etc.
Furthermore, a set of criteria have been developed to anticipate defect formation and embrittlement risk, based on hydrogen supersaturation.
Last but not least, a method has been developed during this work, which enables to reduce hydrogen content from the metal via the use of imposed temperature gradients. This method has recently obtained several patents.
NACE is the corrosion engineer institute. As now, material corrosion exist in our daily life, no matter in the industry application or usual commercial product. They all suffer corrosion impact. As one of member valve industry, I would like to introduce NACE and its related code in upstream and downstream area for stimulating more idea and opponent for make our working environment safe and green.
This is a presentation on hydrogen induced cracking ,sulfide stress cracking and test procedure for HIC resistant steel
DENZIL D’SOUZA
denzil22@gmail.com
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Correlation between Soil Properties and External Corrosion Growth rate of Car...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Heat Transfer, Hardenability and Steel Phase Transformations during Gas Quenc...YuanLu49
https://digitalcommons.wpi.edu/etd-dissertations/399/
"Quenching is the rapid cooling process from an elevated temperature. Compared to water and oil quench medium, high pressure and velocity gas is preferred to quench medium and high hardenability steel, with the potential to reduce distortion, stress and cracks. Currently, no standard test exists to characterize the gas quench steel hardenability and measure the performance of industrial gas quench furnaces. In this thesis, the fundamental difference between the liquid and gas quenching, heat transfer coefficient, was emphasized. It has been proven that gas quenching with constant HTC cannot generate the similar cooling curves compared to liquid quenching. Limitations on current gas quench steel hardenability tests were reviewed. Critical HTC, a concept like critical diameter, was successfully proved to describe the gas quench hardenability of steel. An attempt to use critical HTC test bar and measure the HTC distribution of gas quench furnace was made. Gas quenching, usually with slow cooling rate, may reduce hardness and Charpy impact toughness, compared to water and oil quenching. Lattice parameter and c/a ratio of as-quenched martensite in steel was measured using high resolution X-ray diffraction and Rietveld refinement. For AISI 4140, Charpy impact toughness decreases when the cooling rate decreases after quenching and tempering. Austenite percentage and carbon content in austenite is proposed as the dominated mechanism."
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Portfolio com alguns trabalhos do Publicitário e Designer Felipe Von Zuben que possui experiência internacional em Toronto - Canadá onde desenvolveu trabalhos para importantes equipes e empresas como Toronto Raptors (NBA), Buffalo Bills (NFL), Tennis Canada, Soccer Canada, Toronto Rock, Toronto Rush entre outros.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Correlation between Soil Properties and External Corrosion Growth rate of Car...theijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
The papers for publication in The International Journal of Engineering& Science are selected through rigorous peer reviews to ensure originality, timeliness, relevance, and readability.
Heat Transfer, Hardenability and Steel Phase Transformations during Gas Quenc...YuanLu49
https://digitalcommons.wpi.edu/etd-dissertations/399/
"Quenching is the rapid cooling process from an elevated temperature. Compared to water and oil quench medium, high pressure and velocity gas is preferred to quench medium and high hardenability steel, with the potential to reduce distortion, stress and cracks. Currently, no standard test exists to characterize the gas quench steel hardenability and measure the performance of industrial gas quench furnaces. In this thesis, the fundamental difference between the liquid and gas quenching, heat transfer coefficient, was emphasized. It has been proven that gas quenching with constant HTC cannot generate the similar cooling curves compared to liquid quenching. Limitations on current gas quench steel hardenability tests were reviewed. Critical HTC, a concept like critical diameter, was successfully proved to describe the gas quench hardenability of steel. An attempt to use critical HTC test bar and measure the HTC distribution of gas quench furnace was made. Gas quenching, usually with slow cooling rate, may reduce hardness and Charpy impact toughness, compared to water and oil quenching. Lattice parameter and c/a ratio of as-quenched martensite in steel was measured using high resolution X-ray diffraction and Rietveld refinement. For AISI 4140, Charpy impact toughness decreases when the cooling rate decreases after quenching and tempering. Austenite percentage and carbon content in austenite is proposed as the dominated mechanism."
International Journal of Engineering Research and DevelopmentIJERD Editor
Electrical, Electronics and Computer Engineering,
Information Engineering and Technology,
Mechanical, Industrial and Manufacturing Engineering,
Automation and Mechatronics Engineering,
Material and Chemical Engineering,
Civil and Architecture Engineering,
Biotechnology and Bio Engineering,
Environmental Engineering,
Petroleum and Mining Engineering,
Marine and Agriculture engineering,
Aerospace Engineering.
Portfolio com alguns trabalhos do Publicitário e Designer Felipe Von Zuben que possui experiência internacional em Toronto - Canadá onde desenvolveu trabalhos para importantes equipes e empresas como Toronto Raptors (NBA), Buffalo Bills (NFL), Tennis Canada, Soccer Canada, Toronto Rock, Toronto Rush entre outros.
Самые частые проблемы и пути решения при росте нагрузки и масштабировании про...Andrew Minkin
ы начали делать проект и запустили его в продакшн. Со временем пользователей становится больше и текущих ресурсов вам начинает не хватать. В этом докладе я расскажу о основных путях борьбы с нагрузкой, путях решения и проблемах, связанных с ними.
В докладе мы поговорим о:
0. Что такое нагрузка? Пути борьбы с нагрузкой. Оптимизация кода, кеширование, масштабирование
1. Какие проблемы возникают при внедрении кеширования
2. Как оценивать качество работы кеширования?
3. Путь масштабирования и борьба за ресурсы
4. Проблемы балансировки
5. Проблемы БД. Конкурентный доступ и данным и целостность их
Пути решения проблем будут на примере Python/Django
SERP или просто страница результатов поисковой выдачи — это действительно большой проект с огромной аудиторией. Над ним работают около 40 фронтендеров из разных городов. Эта страница показывается больше 200 000 000 раз в день. При таких размерах даже модульная архитектура уже не слишком спасала нас от странных, неочевидных зависимостей, лишних стилей и нескольких разных реализаций почти одинаковых компонентов.
Процесс разработки новой, даже довольно простой на первый взгляд фичи занимал чудовищное количество времени и представлял из себя хаотичное взаимодействие большого количества людей: фронта, бэкенда, дизайнеров и менеджеров.
Стала закрадываться мысль, что пора что-то менять. И мы поменяли.
В докладе я расскажу о том, как мы с помощью проекта на стыке фронтендеров, менеджеров, и дизайнеров, навели во всем этом идеальный порядок. Каким образом поменяли наш код процессы и инструменты, а также что нам это дало, и как будем жить с этим дальше.
Если вам знакомы похожие проблемы, то наш опыт может оказаться вам чертовски полезным.
Data is becoming an engine for many businesses in the information age, and every company needs to consider look at how that feels in their business model.
This an introductory guest lecture for students at Stockholm School of Entrepreneurship.
UNDERSTANDING AND MITIGATING DOWNHOLE CORROSION AND WEAR FAILURES westernfalcontx
A discussion on different types of corrosion and wear (and their associated mechanisms) followed by an overview of commercially available mitigation techniques, including their practical downhole applications are the focal points of this paper.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Corrosion and Degradation of Materials-chapter 16ssuser2fec01
Cost of Corrosion
Fundamentals of Corrosion
Electrochemical reactions
EMF and Galvanic Series
Concentration and Temperature (Nernst)
Corrosion rate
Corrosion prediction (likelihood)
Polarization
Protection Methods
ASSESSMENT OF CORROSION RATE OF DISSIMILAR WELDED METALS.pdfAfigo Sam
Assessment of rate of corrosion of mild steel, galvanized steel, stainless steel, zinc and dissimilar
welded metals (mild steel and galvanized steel, mild steel and stainless steel, mild steel and zinc,
galvanized steel and stainless steel, galvanized steel and zinc) immersed in acid (0.4 M HCl) and
base (20% NaOH) test solution. The weight loss, corrosion rate and metal loss were determined.
The results of this study revealed that samples corrosion rate increase with increase in exposure
time and galvanic corrosion depends on the standard electrode potential of the samples. The
corrosion rate of the metal plates and dissimilar welded metals immersed in acid test solution (0.4
M HCl) increases in this order; zinc < galvanised steel < mild steel < mild steel and galvanised
steel < mild steel and zinc < galvanised steel and zinc < galvanised and stainless steel < stainless
steel and zinc < mild steel and stainless steel < stainless. The corrosion rate of the metal plates and
dissimilar welded metals immersed in base test solution (20% NaOH) increase in this order;
stainless steel < galvanised < zinc <mild steel and stainless steel < galvanised and stainless steel <
mild steel and galvanised steel < mild steel < galvanised steel and zinc < mild steel and zinc <
stainless steel and zinc. Accelerated galvanic corrosion occur in welded samples of mild steel and
galvanised steel, mild steel and stainless steel, mild steel and zinc, galvanised steel and stainless,
stainless steel and zinc. No accelerated galvanic corrosion was observed in galvanised steel and
zinc.
The inhibition effect of hydralazine hydrochloride on corrosion of mild steel...Premier Publishers
The inhibition effect of the Hydralazine hydrochloride for mild steel corrosion in 1M HCl has been investigated. Polarization measurement indicates that the Hydralazine hydrochloride act as mixed-type inhibitor, which gives a maximum inhibition efficiency around 72 %. Electrochemical impedance spectroscopy was used to investigate the mechanism of corrosion inhibition gives around 76 % due to the formation of electrical double layer. Thermodynamic parameter such as ΔG0 ads value was obtained as -30.22 KJ/mol indications that inhibitor shows its inhibition effect due to the chemisorptions process. Scanning electron microscopic images gives a visual idea about the formation of the protective film on the mild steel surface to reduce the corrosion rate. So that the Hydralazine hydrochloride acts as an efficient mixed type corrosion inhibitor for mild steel corrosion in acid media.
2. PROJECT BACKGROUND
Pipeline Corrosion
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
.
• Welding done along the joints of under water hydrocarbon pipelines.
• Preferential weld corrosion (PWC) occurs in the welded region.
• CO2 triggers PWC.
• Protective layer, FeCO3 precipitation disrupted due to weak acids HAc and pH
• United States , the cost of corrosion in 1986 amounted to US$160 billion.
*R. Barker, X. Hu, A. Neville and S. Cushnaghan, 'Assessment of Preferential Weld Corrosion of Carbon Steel Pipework in CO 2 -Saturated Flow-Induced Corrosion
Environments', Corrosion, vol. 69, no. 11, pp. 1132-1143, 2013.
.
Figure 2 shows the corrosion in the internal part
of the hydrocarbon pipeline
Figure 1: An example of typical weld corrosion
in the pipeline occurred due to CO2 reaction.
3. PROJECT BACKGROUND
Does presence of Acetic Acid (HAc) affect preferentially on the formation of
FeCO3 on to the surfaces of weld segments?
What is the effect of pH value on weld segment corrosion rate with the presence
of Acetic Acid (HAc)?
Problem StatementBackground
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
• R. Barker, X. Hu, A. Neville and S. Cushnaghan, 'Assessment of Preferential Weld Corrosion of Carbon Steel Pipework in CO 2 -Saturated Flow-Induced
Corrosion Environments', Corrosion, vol. 69, no. 11, pp. 1132-1143, 2013
• K. Alawadhi and M. Robinson, 'Preferential weld corrosion of X65 pipeline steel in flowing brines containing carbon dioxide', Corrosion Engineering,
Science and Technology, vol. 46, no. 4, pp. 318-329, 2011..
4. PROJECT BACKGROUND
• To investigate the presence of Acetic Acid (HAc) and its effect on the
corrosion rate of the weld segments.
• To analyze the influence of pH on the FeCO3 formation on the weld segments.
• To perform surface analysis of weld segment under the presence of HAc and
pH influence.
Objectives
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Scope of Study
• Enables to cover one small critical area in the oil and gas industries.
• Help the industry to improve corrosion mitigation method.
• A research to improve the performance and reduce the cost of the industry
• Enhances knowledge and prepare for the real life working culture
5. LITERATURE REVIEW
HAZ
- Base metal exposed to
heat.
- Undergoes microstructure
change
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Figure 3 shows the segments in a weld region
*R. Barker, X. Hu, A. Neville and S. Cushnaghan, 'Assessment of Preferential Weld Corrosion of Carbon Steel Pipework in CO 2
-Saturated Flow-Induced Corrosion Environments', Corrosion, vol. 69, no. 11, pp. 1132-1143, 2013.
Figure 3: The microstructural observation of weld segments using Optical Microscope (OM) with
magnification 50x (a) parent metal (b) HAZ and (c) weld metal.
Parent metal
- Far from welding
- Base metal
Weld metal
- Fusion of filler metal and
PM metal
- Different microstructure.
Preferential Weld Corrosion
6. LITERATURE REVIEW
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
CO2 Corrosion
Figure 4 :Schematic of FeCO3 formation on the steel surface in CO2 environment
Retrieved from:
https:co2corrosionchem409.wikispaces.com/Corrosion+Mechanism?responseToken=a0ebe1b916b14bc311c48f0f73fde1c9//
*C. de Waard, D.E. Milliams, Corrosion 31, 5 (1975): p. 175.
* S. Nes˘ic´, G.T. Solvi, J. Enerhaug, Corrosion 51, 10 (1995): p. 773.
7. LITERATURE REVIEW
Acetic Acid in CO2 corrosion
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
References Findings
J.-L. Crolet,
N. Thevenot,
A. Dugstad,
(1999)
• A type of weak acid
• Short carboxylic chains
• The hydrogen center in the carboxyl group (−COOH) easily
separates by ionization:
CH3CO2H → CH3CO2− + H+
S. Nes˘ic´,
G.T. Solvi, J.
Enerhaug,
(1995)
• Partially soluble. Reservoir for H+ supply.
• Undissociated free HAc causes reduction of Hydrogen ion.
2H
+
2e−
→ H2
(cathodic reaction)
• Decreases the pH of the condensate → Solubility of iron.
Fe → Fe
2
+
+ 2e−
(anodic reaction)
8. LITERATURE REVIEW
Acetic Acid in FeCO3 formation
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation High
Temperature
High HAc
concentration
undergoing partial
ionization
Fe(CH3
COOH)2(s)
+ H2
(g)
FeCO3 layer
fail to form
High rate
of
corrosion
Reference Findings
R. Nyborg
and A.
Dugstad
(2007)
• Increases the solubility of iron due to un-dissociated HAc (Iron
Acetate formation)
Fe(s) + 2CH3
COOH(aq) → Fe(CH3
COOH)2(s) + H2
(g)
• Fe(CH3
COOH)2(s) is highly soluble, does not precipitate.
• FeCO3 formation is disrupted.
9. LITERATURE REVIEW
pH influence in the HAc reaction
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
References Findings
Hedges and McVeigh (1999) At low pH (4-5)
• thin FeCO3 formation
• HAc mostly forms Fe(CH3
COOH)2(s)
• Corrosion rate increases
A high pH (5-6)
• Less FeCO3 solubility
• Corrosion rate decreases
(fully mitigated if HAc is below 400ppm)
10. LITERATURE REVIEW
pH influence in the HAc reaction
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
References Findings
K.S. George*
and S. Nes˘ic
(2007)
At low pH (4-5)
• High concentration of HAc
• influences high anodic reaction
Fe → Fe
2
+
+ 2e−
A high pH (5-6)
• Less HAc concentration
• less anodic reaction, yet slow cathodic
2H
+
2e−
→ H2
Figure 5: The effect of pH on potentiodynamic sweeps
done on X65 steel corroding in aqueous solutions purged
with CO2 containing 100 ppm total acetic species at
1,000 rpm, 22°C.
Retrieved; *K. George and S. Nesic, 'Investigation of
Carbon Dioxide Corrosion of Mild Steel in the presence of
Acetic Acid', NACE International, vol., 2007
11. Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Total Corrosion Rate
Type of corrosion Measurements
Connection Diagram
Intrinsic Corrosion • Self-corrosion undergone by a metal.
Galvanic Corrosion • Corrosion due to potential difference between
metal segments.
Total Corrosion [CRTotal = CRIntrinsic + CRGalvanic]
LITERATURE REVIEW
*A.E. Jenkins, W.Y. Mok, C.G. Gamble, Baker Petrolite; G.E. Dicken, CAPCIS, “Development of Green Corrosion Inhibitors for Preventing Under Deposit and Weld
Corrosion, Paper no. 87558-MS,” Presented at 2004 SPE International Symposium on Oilfield Corrosion, Aberdeen, United Kingdom.
*K. Alawadhi, M. Robinson, A. Chalmers, and I.G. Winning, “Inhibition of weld corrosion in flowing brines containing carbon dioxide, Paper no. 622,” Presented at 2008
NACE Conference.
14. METHODOLOGY
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Test Parameters to investigate the weld segments corrosion behavior.
Parameters Test 1 Test 2 Test 3 Test 4
Brine 3 wt.% aqueous NaCl
Carbon Steel API 5L X52
Partial pressure (bar) 0.53
Temperature (OC) 80
Concentration of acetic acid
(ppm)
0 0 1000 1000
pH 4 6.6 4 6.6
15. METHODOLOGY
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Method of Conduction
Method Measurements Connection Diagram
Linear
Polarization
Resistance
(LPR)
LPR method will be used to
measure corrosion rate
between the weld samples.
Zero
Resistance
Ammeter
(ZRA)
To measure the galvanic
current of each weld region at
specific time galvanic current
density is performed.
16. METHODOLOGY
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Techniques of evaluation
Sample Techniques Results obtained Glass cell Connections
Un-
coupled
Linear Polarization
Resistance (LPR)
Intrinsic Corrosion sweep
(mm/yr)
Current & Voltage / time Potential (mV) & Galvanic
reading (mA/cm²)
Coupled Linear Polarization
Resistance (LPR)
Galvanic Corrosion sweep
(mm/yr)
Current & Voltage / time Potential (mV) & Galvanic
reading (mA/cm²)
Zero Resistance Ammeter
(ZRA)
[IPM
+ IHAZ
+ IWM
= 0]
Current weld
measurement
(mA/cm²)
Total
corrosion [CRTotal = CRIntrinsic + CRGalvanic]
Total corrosion rate
(mm/yr)
17. RESULTS AND DISCUSSION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Summary of intrinsic corrosion behavior of weld segments
Intrinsic Corrosion Rate [mm/yr]
Segment Parent HAZ Weld
Test 1 0.10 <0.1 0.05
Test 2 0.01 <0.1 <0.1
Test 3 0.01 <0.1 <0.1
Test 4 0.02 <0.1 0.02
Discussion
• Parent metal has the highest
rate of intrinsic corrosion.
• HAZ faces least intrinsic
corrosion rate <0.1mm/yr.
• Weld corrosion highest
corrosion rate in Test 1 and
Test 4. <0.1mm/yr corrosion
rate for Test 2 and 3.
18. RESULTS AND DISCUSSION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Summary of galvanic corrosion between the weld segments.
Galvanic Corrosion Rate [mm/yr]
Segment Parent HAZ Weld
Test 1 <0.1 1.70 0.87
Test 2 0.12 3.80 2.72
Test 3 <0.1 5.25 5.51
Test 4 0.03 3.88 2.04
Discussion
• Weld metal has highest
galvanic corrosion rate in
Test 3 of 5.51 mm/yr.
• HAZ has the highest
galvanic corrosio in Test 3
with 5.25 mm/yr.
• Weld Metal and HAZ has
similar behavior of
galvanic corrosion.
• Parent metal has low
galvanic corrosion rate
throughout. Highest of 0.12
mm/yr in Test 2.
19. RESULTS AND DISCUSSION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Total corrosion rate of parent metal
Total
corrosion
rate
(mm/yr) pH
HAc
(ppm)
Test 1 0.10 4 0
Test 2 0.13 6.6 0
Test 3 <0.1 4 1000
Test 4 0.05 6.6 1000
Discussion
• Highest total corrosion rate of 0.13 mm/yr in Test 2.
• Least total corrosion occurred in Test 3; below 0.1 mm/yr.
20. RESULTS AND DISCUSSION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Total corrosion rate of Heat Affected Zone
Discussion
• Highest total corrosion rate of 5.25 mm/yr in Test 3.
• Lowest total corrosion rate of 1.7 mm/yr in Test 2.
Total
corrosion
rate
(mm/yr) pH
HAc
(ppm)
Test 1 3.8 4 0
Test 2 1.7 6.6 0
Test 3 5.25 4 1000
Test 4 3.88 6.6 1000
21. RESULTS AND DISCUSSION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Test
Total
corrosion
rate
HAc
(ppm) pH
1 2.72 0 4
2 0.92 0 6.6
3 5.51 1000 4
4 2.06 1000 6.6
Total corrosion rate of Weld Metal
Discussion
• Highest total corrosion rate of 5.51 mm/yr in Test 3.
• Lowest total corrosion rate of 0.97 mm/yr in Test 2.
• Similar to the total corrosion rate pattern of HAZ.
22. RESULTS AND DISCUSSION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Effect of pH influence
Test
Total
corrosio
n rate
HAc
(ppm)
1 2.72 0
2 0.92 0
3 5.51 1000
4 2.06 1000
• Test 1 corrosion rate is higher with pH 4 compared to Test 2 with pH 6.6.
• Increase in pH has lowered the corrosion rate by 66%.
• Test 3 has higher total corrosion rate with pH 4 compared to Test 4 with pH
6.6 with HAc present.
• The pH increment has mitigated the total corrosion rate by 62%.
23. RESULTS AND DISCUSSION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Surface Morphology of pH effect comparing Test 1 and Test 2
Test 1 coupled specimen surface morphology of (a) parent steel, (b) HAZ and (c)
weld metal after 24 hours LPR test under 1000x magnification.
Test 2 coupled specimen surface morphology of (a) parent steel, (b) HAZ and
(c) weld metal after 24 hours LPR test under 1000x magnification.
24. RESULTS AND DISCUSSION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Surface Morphology of pH effect comparing Test 3 and Test 4
Test 3 coupled specimen surface morphology of (a) parent steel, (b) HAZ and (c)
weld metal after 24 hours LPR test under 1000x magnification.
Test 4 coupled specimen surface morphology of (a) parent steel, (b) HAZ and
(c) weld metal after 24 hours LPR test under 1000x magnification.
25. RESULTS AND DISCUSSION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Effect of HAc presence
Test
Total
corrosio
n rate
HAc
(ppm)
1 2.72 0
2 0.92 0
3 5.51 1000
4 2.06 1000
• Total corrosion rate of Test 3 has increased with the presence of HAc
comparing Test 1 total corrosion rate without HAc present.
• Total corrosion rate has increased by 50% with the HAc presence.
• Test 4 total corrosion rate is higher with the presence of HAc compared with
Test 2 without.
• Presence of HAc has increased the total corrosion rate by 55%.
26. RESULTS AND DISCUSSION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Surface Morphology HAc presence comparing Test 1 and Test 3
Test 3 coupled specimen surface morphology of (a) parent steel, (b) HAZ and (c)
weld metal after 24 hours LPR test under 1000x magnification.
Test 1 coupled specimen surface morphology of (a) parent steel, (b) HAZ and (c)
weld metal after 24 hours LPR test under 1000x magnification.
27. RESULTS AND DISCUSSION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Surface Morphology of FeCO3 thickness for Test 2 (without HAc presence)
Figure 34: SEM micrograph showing the cross section of the FeCO3 layer formed
coupled sample under Test 2 experimental conditions. (a) parent metal surface;(b)
HAZ surface;(c) weld metal surface;(d) EDX results.
28. RESULTS AND DISCUSSION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Surface Morphology of FeCO3 thickness for Test 4 (with 1000ppm HAc)
Figure 35: SEM micrograph showing the cross section of the FeCO3 layer
formed coupled sample under Test 4 experimental conditions. (a) parent metal
surface;(b) HAZ surface;(c) weld metal surface;(d) EDX results.
29. CONCLUSION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
Analytical
criteria
CRTotal Surface analysis Film
Formation
Cross section
film thickness
Test 1 3 (Corroded PM,HAZ) 3 WM
Test 2 4 (Protected) 4 PM, HAZ, WM Uniform Thin
film formation
HAZ>PM>WM
Test 3 1 (Corroded WM, HAZ) 1 PM
Test 4 2 (Corroded WM) 2 PM, HAZ Spots of thick
film formation
on PM
surface.
No. Weightage
1 Very High
2 High
3 Low
4 Very Low
• WM and HAZ highly affected by PWC in presence of HAc
• pH influences the carbonate formation with and wihout
the presence of HAc
• Presence of HAc causes corrosion rate to increase.
• Low pH and HAc presence gives high corrosion rate
30. RECOMMENDATION
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
1. Identify the formation of the protective film that has formed on the
surface of the parent metal under low pH with HAc present.
2. Conduction of tests to investigate the HAc under varying temperature of
25oC and 60oC.
3. Investigate the formation of FeCO3 layer under different concentrations
of HAc such as 85 ppm and 850 ppm under constant pH of 6.6.
31. METHODOLOGY
Gantt Chart
▲Expected Milestones Table 4: FYP I Gantt Chart
and Key Milestones
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation
32. METHODOLOGY
Gantt Chart
▲Expected Milestones Table 5: FYP II Gantt Chart
and Key Milestones
Background
Literature Review
Methodology
Results &
Discussion
Conclusion &
Recommendation