Dr. Shagufta Khan presented on understanding end grain corrosion in austenitic stainless steels. End grain corrosion occurs preferentially at grain boundaries and is caused by segregation of elements like silicon and phosphorus along the boundaries. It is a problem in nuclear reprocessing plants where stainless steel tubing is exposed to highly oxidizing nitric acid. Laser remelting and weld overlays can be used to control end grain corrosion by modifying the microstructure and masking susceptible material, while solution annealing homogenizes the material's structure.
Effect of Surface Hardening Technique and Case Depth on Rolling Contact Fatig...Dave Palmer, P.E.
Surface hardening techniques are widely used to improve the rolling contact fatigue resistance of materials. This study investigated the rolling contact fatigue (RCF) resistance of hardened, ground steel rods made from three different aircraft-quality alloy steels (AISI 8620, 9310 and 4140), and hardened using different techniques (atmosphere carburizing, vacuum carburizing, and induction hardening) at different case depths. The fatigue life of the rods was determined using a three ball-on-rod rolling contact fatigue test machine. After testing, the surfaces of the rods were examined using scanning electron microscopy (SEM), and their microstructures were examined using metallographic techniques. In addition, the surface topography of the rods was measured using white-light interferometry. Relationships between surface hardness, case depth, and fatigue life were investigated. The longest lives were observed for the vacuum carburized AISI 9310 specimens, while the shortest lives were observed for the induction hardened AISI 4140 specimens. It was found the depth to a hardness of 613 HV (56 HRC), as opposed to the traditional definition of case depth as the depth to a hardness of 513 HV (50 HRC), provided a somewhat better correlation to RCF life, and the hardness at a depth of 0.254 mm provided a somewhat better correlation than the surface hardness to RCF life.
Effect of Surface Hardening Technique and Case Depth on Rolling Contact Fatig...Dave Palmer, P.E.
Surface hardening techniques are widely used to improve the rolling contact fatigue resistance of materials. This study investigated the rolling contact fatigue (RCF) resistance of hardened, ground steel rods made from three different aircraft-quality alloy steels (AISI 8620, 9310 and 4140), and hardened using different techniques (atmosphere carburizing, vacuum carburizing, and induction hardening) at different case depths. The fatigue life of the rods was determined using a three ball-on-rod rolling contact fatigue test machine. After testing, the surfaces of the rods were examined using scanning electron microscopy (SEM), and their microstructures were examined using metallographic techniques. In addition, the surface topography of the rods was measured using white-light interferometry. Relationships between surface hardness, case depth, and fatigue life were investigated. The longest lives were observed for the vacuum carburized AISI 9310 specimens, while the shortest lives were observed for the induction hardened AISI 4140 specimens. It was found the depth to a hardness of 613 HV (56 HRC), as opposed to the traditional definition of case depth as the depth to a hardness of 513 HV (50 HRC), provided a somewhat better correlation to RCF life, and the hardness at a depth of 0.254 mm provided a somewhat better correlation than the surface hardness to RCF life.
A presentation giving the basic principles of corrosion. Electrochemical nature of corrosion, anodic and cathodic reactions, electrode potentials, mixed potential theory and kinetics of corrosion, thermodynamics of corrosion and Pourbaix diagrams, and passivization behavior of metals are outlined.
This presentation gives a brief introduction to chemical heat treatment of steels and surface hardening techniques
Keywords: Carburising, Nitriding, Carbonitriding, Flame hardening, Laser hardening, Induction hardening
This topic includes various aspects regarding Corrosion prevention. It includes material of construction, how environment changes and its effect on corrosion, how can we properly design our equipment to avoid from corrosion. It also includes Cathodic protection and Anodic protection.
Thermal Barrier Coating For Gas Turbine EnginesNelsonkandulna
This presentation describes the thermal barrier coating process, its anatomy, types, material selection, failure, and characterization. Thermal barrier coatings (TBCs) were introduced to protect the external surface of gas turbine engine components from thermal resistance and thereby decrease the temperature of the metal surfaces. Yttria stabilized zirconia (YSZ) is one of the most popular and widely used TBC materials as it provides the best performance in high-temperature zones such as diesel engines and gas turbines. The columnar microstructure of YSZ coating provides excellent strain tolerance and adhesion to the coating. Gas turbines are used to power aircraft, trains, ships, electrical generators, pumps, gas compressors, and tanks.
A presentation giving the basic principles of corrosion. Electrochemical nature of corrosion, anodic and cathodic reactions, electrode potentials, mixed potential theory and kinetics of corrosion, thermodynamics of corrosion and Pourbaix diagrams, and passivization behavior of metals are outlined.
This presentation gives a brief introduction to chemical heat treatment of steels and surface hardening techniques
Keywords: Carburising, Nitriding, Carbonitriding, Flame hardening, Laser hardening, Induction hardening
This topic includes various aspects regarding Corrosion prevention. It includes material of construction, how environment changes and its effect on corrosion, how can we properly design our equipment to avoid from corrosion. It also includes Cathodic protection and Anodic protection.
Thermal Barrier Coating For Gas Turbine EnginesNelsonkandulna
This presentation describes the thermal barrier coating process, its anatomy, types, material selection, failure, and characterization. Thermal barrier coatings (TBCs) were introduced to protect the external surface of gas turbine engine components from thermal resistance and thereby decrease the temperature of the metal surfaces. Yttria stabilized zirconia (YSZ) is one of the most popular and widely used TBC materials as it provides the best performance in high-temperature zones such as diesel engines and gas turbines. The columnar microstructure of YSZ coating provides excellent strain tolerance and adhesion to the coating. Gas turbines are used to power aircraft, trains, ships, electrical generators, pumps, gas compressors, and tanks.
International Journal of Engineering Research and Development (IJERD)IJERD Editor
International Journal of Engineering Research and Development is an international premier peer reviewed open access engineering and technology journal promoting the discovery, innovation, advancement and dissemination of basic and transitional knowledge in engineering, technology and related disciplines.
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.
Event Management System Vb Net Project Report.pdfKamal Acharya
In present era, the scopes of information technology growing with a very fast .We do not see any are untouched from this industry. The scope of information technology has become wider includes: Business and industry. Household Business, Communication, Education, Entertainment, Science, Medicine, Engineering, Distance Learning, Weather Forecasting. Carrier Searching and so on.
My project named “Event Management System” is software that store and maintained all events coordinated in college. It also helpful to print related reports. My project will help to record the events coordinated by faculties with their Name, Event subject, date & details in an efficient & effective ways.
In my system we have to make a system by which a user can record all events coordinated by a particular faculty. In our proposed system some more featured are added which differs it from the existing system such as security.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
Explore the innovative world of trenchless pipe repair with our comprehensive guide, "The Benefits and Techniques of Trenchless Pipe Repair." This document delves into the modern methods of repairing underground pipes without the need for extensive excavation, highlighting the numerous advantages and the latest techniques used in the industry.
Learn about the cost savings, reduced environmental impact, and minimal disruption associated with trenchless technology. Discover detailed explanations of popular techniques such as pipe bursting, cured-in-place pipe (CIPP) lining, and directional drilling. Understand how these methods can be applied to various types of infrastructure, from residential plumbing to large-scale municipal systems.
Ideal for homeowners, contractors, engineers, and anyone interested in modern plumbing solutions, this guide provides valuable insights into why trenchless pipe repair is becoming the preferred choice for pipe rehabilitation. Stay informed about the latest advancements and best practices in the field.
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
Quality defects in TMT Bars, Possible causes and Potential Solutions.PrashantGoswami42
Maintaining high-quality standards in the production of TMT bars is crucial for ensuring structural integrity in construction. Addressing common defects through careful monitoring, standardized processes, and advanced technology can significantly improve the quality of TMT bars. Continuous training and adherence to quality control measures will also play a pivotal role in minimizing these defects.
COLLEGE BUS MANAGEMENT SYSTEM PROJECT REPORT.pdfKamal Acharya
The College Bus Management system is completely developed by Visual Basic .NET Version. The application is connect with most secured database language MS SQL Server. The application is develop by using best combination of front-end and back-end languages. The application is totally design like flat user interface. This flat user interface is more attractive user interface in 2017. The application is gives more important to the system functionality. The application is to manage the student’s details, driver’s details, bus details, bus route details, bus fees details and more. The application has only one unit for admin. The admin can manage the entire application. The admin can login into the application by using username and password of the admin. The application is develop for big and small colleges. It is more user friendly for non-computer person. Even they can easily learn how to manage the application within hours. The application is more secure by the admin. The system will give an effective output for the VB.Net and SQL Server given as input to the system. The compiled java program given as input to the system, after scanning the program will generate different reports. The application generates the report for users. The admin can view and download the report of the data. The application deliver the excel format reports. Because, excel formatted reports is very easy to understand the income and expense of the college bus. This application is mainly develop for windows operating system users. In 2017, 73% of people enterprises are using windows operating system. So the application will easily install for all the windows operating system users. The application-developed size is very low. The application consumes very low space in disk. Therefore, the user can allocate very minimum local disk space for this application.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Vaccine management system project report documentation..pdfKamal Acharya
The Division of Vaccine and Immunization is facing increasing difficulty monitoring vaccines and other commodities distribution once they have been distributed from the national stores. With the introduction of new vaccines, more challenges have been anticipated with this additions posing serious threat to the already over strained vaccine supply chain system in Kenya.
Vaccine management system project report documentation..pdf
Intergranular corrosion in SS tubes
1. Understanding End Grain Corrosion in Austenitic Stainless Steels
Dr Shagufta Khan
Organized by
Eventagious Conference & Exhibition (ConEx)
virtual summit on
“ALL ABOUT CORROSION”
27th November, 2020
2. Dr Shagufta Khan
Present Company: AMCO Integrity Pty Ltd
Name & : Dr Shagufta Khan
Designation: Director Asset Integrity and Corrosion
Academic
Qualification: Ph.D. Corrosion engineering
Specialized Knowledge: Asset Integrity and Corrosion
Achievements: 18 Publications in international journals and conference proceedings
Guest editor for [Sustainability] Special Issue - Sustainable Materials,
Manufacturing and Design.
Key points of the Paper
3. Introduction
• Austenitic stainless steels (SS) are routinely specified for nitric acid (HNO3)
duty in nuclear reprocessing plants, owing to their passivity.
• However, in sufficiently oxidizing conditions generated either by high
temperatures or the presence of dissolved species such as oxydising ions,
passivity is lost and high corrosion rates can result.
• Such trans passive corrosion is morphologically characterized as
intergranular corrosion.
4. Operating parameters in the plant
Process parameters
• Nitric acid of varying concentration
• Temperatures up to boiling point (110
oC)
• Oxidizing ions
Material parameters
• Material used
(mainly SS 304L & SS 304L
(NAG))
• Sensitization
• Exposed surface
• Cold working
• Element segregation
5. Improved corrosion resistance of type 304 L
stainless steel – nitric acid grade
Element Composition, Wt.%
304L CP 304L NAG
C < 0.03 < 0.025
Si < 1.0 < 0.25
Mn < 2.0 < 2.0
P < 0.045 < 0.018
S < 0.03 < 0.015
Cr 18 – 20 18 – 20
Ni 8 – 12 9 - 11
O ~100 ppm < 50 ppm
N < 500 ppm < 200 ppm
Control of:
Intergranular corrosion:
Sensitization - levels of C,
Ni and Cr and Si & P
End Grain Corrosion:
Sulfide inclusions and
segregation of Cr, Si and P
Uniform Corrosion:
Controlled cold work
9. Causes of Intergranular Corrosion
• The enhanced susceptibility of grain boundaries largely
due to segregation of silicon and phosphorus.
• Grain boundary attack also can result from local
chromium depletion (sensitization) brought about by the
precipitation of chromium carbides (Cr23C6) during
various thermal treatments such as welding.
• Sensitization is of little significance for modern steels
where carbon is controlled to very low levels
• The corrosion rate of SS in HNO3 usually depends on the
orientation of the exposed surface. Generally, the
corrosion rate increases in the order: plate < side << end
10. How to prevent intergranular corrosion?
• Use low carbon (e.g. 304L, 316L) grade of stainless steels
• Use stabilized grades alloyed with titanium (for example type 321) or
niobium (for example type 347). Titanium and niobium are strong
carbide- formers. They react with the carbon to form the corresponding
carbides thereby preventing chromium depletion.
• Use post-weld heat treatment.
• Chemical composition based parameter Cr effective ( = % Cr - 0.18 (% Ni)
- 100 (% C)) with values greater than 14.0 indicating resistance to
intergranular corrosion of austenitic stainless steels in its welded
condition.
• Refinement in grain size
11. In reprocessing plants instrument tubing,
tube to tube sheet welds, Forgings and set
in pipe branches are reported to be most
affected by end grain corrosion.
Exposure studies done in a dissolver in a
reprocessing plant (in vapor phase) showed
very heavy corrosion rates of 0.6 – 2 mm/y
even for NAG grade of stainless steel and
was attributed mainly to end grain
corrosion.
End grain corrosion is specifically related
to highly oxidizing nitric acid environments.
End Grain Corrosion
12. Morphology of End Grain Corrosion
End grain corrosion in 304L stainless steel after exposure to practice C, A262, ASTM
(a) From the longitudinal direction (b) From the cross section.
(a) (b)
13. Causes of End Grain Corrosion
Inclusions in the form of stringers cause IGC in austenitic stainless steels.
Segregated elements along dislocations due to cold working and insufficient
solution annealing may be preferential site of end grain corrosion attack.
Segregation of P along the grain boundary in 304L steel has resulted in severe end
grain corrosion in nitric acid medium.
Segregation of P along the grain boundary in 304L steel has resulted in severe end
grain corrosion in nitric acid medium.
Presence of highly oxidizing medium
14. End grain corrosion rate as a function of time at two
different concentration of Cr (VI) in 9 M HNO3
Corrosion
rate
(mm/y)
15. Potential variation with time in 9 M boiling solution of
nitric acid containing different concentration of Cr +6.
16. • Modification of
microstructure of the
end faces after laser
remelting.
• The elongated
inclusions and
segregation of Cr, Si,
and P along the flow
lines get eliminated.
• Presence of delta
ferrite in the melt
pool
Control of End Grain Corrosion by laser surface remelting
Control of end grain corrosion
17. • Weld deposition on
the end faces masks
the susceptible
material (to end-grain
corrosion) with a more
corrosion resistant
material.
• This helps in increasing
the corrosion
resistance of the
component.
Control of End Grain Corrosion by weld overlay on
the exposed end faces.
Control of end grain corrosion
18. Control of end grain corrosion
• Solution annealing is known to homogenize the structure of the
material. Therefore, it should minimize the end-grain corrosion of
the material occurring due to chemical inhomogenity.
• The temperature and time for the heat treatment is selected to
minimize grain growth while permitting elemental diffusion to take
place for homogenization of elemental segregation at flow lines.
• Solution annealing at 950 0C for 90 minutes has been shown to be
effective in 304 L.